From 92c35a0617836b09aef3b6909579ee368004969b Mon Sep 17 00:00:00 2001 From: Malcolm Tredinnick Date: Mon, 21 May 2007 01:29:58 +0000 Subject: [PATCH] Fixed #2365, #3324 -- Renamed FloatField to DecimalField and changed the code to return Decimal instances in Python for this field. Backwards incompatible change. Added a real FloatField (stores floats in the database) and support for FloatField and DecimalField in newforms (analogous to IntegerField). Included decimal.py module (as django.utils._decimal) from Python 2.4. This is license compatible with Django and included for Python 2.3 compatibility only. Large portions of this work are based on patches from Andy Durdin and Jorge Gajon. git-svn-id: http://code.djangoproject.com/svn/django/trunk@5302 bcc190cf-cafb-0310-a4f2-bffc1f526a37 --- AUTHORS | 2 +- .../contrib/admin/templatetags/admin_list.py | 4 +- django/contrib/admin/views/doc.py | 3 +- django/core/management.py | 8 +- django/core/serializers/json.py | 42 +- django/core/validators.py | 28 +- django/db/backends/ado_mssql/creation.py | 3 +- django/db/backends/mysql/base.py | 4 +- django/db/backends/mysql/creation.py | 3 +- django/db/backends/mysql/introspection.py | 2 +- django/db/backends/mysql_old/base.py | 2 + django/db/backends/mysql_old/creation.py | 3 +- django/db/backends/mysql_old/introspection.py | 2 +- django/db/backends/oracle/creation.py | 3 +- django/db/backends/oracle/introspection.py | 2 +- django/db/backends/postgresql/base.py | 1 + django/db/backends/postgresql/creation.py | 3 +- .../db/backends/postgresql/introspection.py | 3 +- .../postgresql_psycopg2/introspection.py | 3 +- django/db/backends/sqlite3/base.py | 7 + django/db/backends/sqlite3/creation.py | 3 +- django/db/backends/util.py | 15 + django/db/models/fields/__init__.py | 73 +- django/newforms/fields.py | 68 +- django/oldforms/__init__.py | 30 +- django/utils/_decimal.py | 3079 +++++++++++++++++ docs/forms.txt | 7 +- docs/model-api.txt | 48 +- docs/newforms.txt | 8 +- tests/modeltests/invalid_models/models.py | 10 +- tests/regressiontests/forms/tests.py | 131 + .../serializers_regress/models.py | 16 +- .../serializers_regress/tests.py | 71 +- 33 files changed, 3579 insertions(+), 108 deletions(-) create mode 100644 django/utils/_decimal.py diff --git a/AUTHORS b/AUTHORS index 66b19c2659..cd54dbad08 100644 --- a/AUTHORS +++ b/AUTHORS @@ -41,7 +41,6 @@ And here is an inevitably incomplete list of MUCH-APPRECIATED CONTRIBUTORS -- people who have submitted patches, reported bugs, added translations, helped answer newbie questions, and generally made Django that much better: - adurdin@gmail.com alang@bright-green.com Marty Alchin Daniel Alves Barbosa de Oliveira Vaz @@ -90,6 +89,7 @@ answer newbie questions, and generally made Django that much better: dne@mayonnaise.net Maximillian Dornseif Jeremy Dunck + Andrew Durdin Andy Dustman Clint Ecker enlight diff --git a/django/contrib/admin/templatetags/admin_list.py b/django/contrib/admin/templatetags/admin_list.py index 5c678fba6f..0bf18d86cc 100644 --- a/django/contrib/admin/templatetags/admin_list.py +++ b/django/contrib/admin/templatetags/admin_list.py @@ -166,8 +166,8 @@ def items_for_result(cl, result): # Booleans are special: We use images. elif isinstance(f, models.BooleanField) or isinstance(f, models.NullBooleanField): result_repr = _boolean_icon(field_val) - # FloatFields are special: Zero-pad the decimals. - elif isinstance(f, models.FloatField): + # DecimalFields are special: Zero-pad the decimals. + elif isinstance(f, models.DecimalField): if field_val is not None: result_repr = ('%%.%sf' % f.decimal_places) % field_val else: diff --git a/django/contrib/admin/views/doc.py b/django/contrib/admin/views/doc.py index 6adfb57c92..6430252690 100644 --- a/django/contrib/admin/views/doc.py +++ b/django/contrib/admin/views/doc.py @@ -294,10 +294,11 @@ DATA_TYPE_MAPPING = { 'CommaSeparatedIntegerField': _('Comma-separated integers'), 'DateField' : _('Date (without time)'), 'DateTimeField' : _('Date (with time)'), + 'DecimalField' : _('Decimal number'), 'EmailField' : _('E-mail address'), 'FileField' : _('File path'), 'FilePathField' : _('File path'), - 'FloatField' : _('Decimal number'), + 'FloatField' : _('Floating point number'), 'ForeignKey' : _('Integer'), 'ImageField' : _('File path'), 'IntegerField' : _('Integer'), diff --git a/django/core/management.py b/django/core/management.py index 327796dc14..e72f05e314 100644 --- a/django/core/management.py +++ b/django/core/management.py @@ -870,7 +870,7 @@ def inspectdb(): if field_type == 'CharField' and row[3]: extra_params['maxlength'] = row[3] - if field_type == 'FloatField': + if field_type == 'DecimalField': extra_params['max_digits'] = row[4] extra_params['decimal_places'] = row[5] @@ -945,11 +945,11 @@ def get_validation_errors(outfile, app=None): e.add(opts, '"%s": You can\'t use "id" as a field name, because each model automatically gets an "id" field if none of the fields have primary_key=True. You need to either remove/rename your "id" field or add primary_key=True to a field.' % f.name) if isinstance(f, models.CharField) and f.maxlength in (None, 0): e.add(opts, '"%s": CharFields require a "maxlength" attribute.' % f.name) - if isinstance(f, models.FloatField): + if isinstance(f, models.DecimalField): if f.decimal_places is None: - e.add(opts, '"%s": FloatFields require a "decimal_places" attribute.' % f.name) + e.add(opts, '"%s": DecimalFields require a "decimal_places" attribute.' % f.name) if f.max_digits is None: - e.add(opts, '"%s": FloatFields require a "max_digits" attribute.' % f.name) + e.add(opts, '"%s": DecimalFields require a "max_digits" attribute.' % f.name) if isinstance(f, models.FileField) and not f.upload_to: e.add(opts, '"%s": FileFields require an "upload_to" attribute.' % f.name) if isinstance(f, models.ImageField): diff --git a/django/core/serializers/json.py b/django/core/serializers/json.py index 7c029e7029..20adce798d 100644 --- a/django/core/serializers/json.py +++ b/django/core/serializers/json.py @@ -4,19 +4,24 @@ Serialize data to/from JSON import datetime from django.utils import simplejson +from django.utils.simplejson import decoder from django.core.serializers.python import Serializer as PythonSerializer from django.core.serializers.python import Deserializer as PythonDeserializer try: from cStringIO import StringIO except ImportError: from StringIO import StringIO +try: + import decimal +except ImportError: + from django.utils import _decimal as decimal # Python 2.3 fallback class Serializer(PythonSerializer): """ Convert a queryset to JSON. """ def end_serialization(self): - simplejson.dump(self.objects, self.stream, cls=DateTimeAwareJSONEncoder, **self.options) + simplejson.dump(self.objects, self.stream, cls=DjangoJSONEncoder, **self.options) def getvalue(self): if callable(getattr(self.stream, 'getvalue', None)): @@ -30,12 +35,13 @@ def Deserializer(stream_or_string, **options): stream = StringIO(stream_or_string) else: stream = stream_or_string + #for obj in PythonDeserializer(simplejson.load(stream, cls=DjangoJSONDecoder)): for obj in PythonDeserializer(simplejson.load(stream)): yield obj -class DateTimeAwareJSONEncoder(simplejson.JSONEncoder): +class DjangoJSONEncoder(simplejson.JSONEncoder): """ - JSONEncoder subclass that knows how to encode date/time types + JSONEncoder subclass that knows how to encode date/time and decimal types. """ DATE_FORMAT = "%Y-%m-%d" @@ -48,5 +54,33 @@ class DateTimeAwareJSONEncoder(simplejson.JSONEncoder): return o.strftime(self.DATE_FORMAT) elif isinstance(o, datetime.time): return o.strftime(self.TIME_FORMAT) + elif isinstance(o, decimal.Decimal): + return str(o) else: - return super(DateTimeAwareJSONEncoder, self).default(o) + return super(DjangoJSONEncoder, self).default(o) + +# Older, deprecated class name (for backwards compatibility purposes). +DateTimeAwareJSONEncoder = DjangoJSONEncoder + +## Our override for simplejson.JSONNumber, because we want to use decimals in +## preference to floats (we can convert decimal -> float when they stored, if +## needed, but cannot go the other way). +#def DjangoNumber(match, context): +# match = DjangoNumber.regex.match(match.string, *match.span()) +# integer, frac, exp = match.groups() +# if exp: +# res = float(integer + (frac or '') + (exp or '')) +# elif frac: +# res = decimal.Decimal(integer + frac) +# else: +# res = int(integer) +# return res, None +#decoder.pattern(r'(-?(?:0|[1-9]\d*))(\.\d+)?([eE][-+]?\d+)?')(DjangoNumber) +# +#converters = decoder.ANYTHING[:] +#converters[-1] = DjangoNumber +#decoder.JSONScanner = decoder.Scanner(converters) +# +#class DjangoJSONDecoder(simplejson.JSONDecoder): +# _scanner = decoder.Scanner(converters) +# diff --git a/django/core/validators.py b/django/core/validators.py index 26165c4af1..293f0e1a8c 100644 --- a/django/core/validators.py +++ b/django/core/validators.py @@ -25,6 +25,7 @@ email_re = re.compile( r"(^[-!#$%&'*+/=?^_`{}|~0-9A-Z]+(\.[-!#$%&'*+/=?^_`{}|~0-9A-Z]+)*" # dot-atom r'|^"([\001-\010\013\014\016-\037!#-\[\]-\177]|\\[\001-011\013\014\016-\177])*"' # quoted-string r')@(?:[A-Z0-9-]+\.)+[A-Z]{2,6}$', re.IGNORECASE) # domain +decimal_re = re.compile(r'^-?(?P\d+)(\.(?P\d+))?$') integer_re = re.compile(r'^-?\d+$') ip4_re = re.compile(r'^(25[0-5]|2[0-4]\d|[0-1]?\d?\d)(\.(25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}$') phone_re = re.compile(r'^[A-PR-Y0-9]{3}-[A-PR-Y0-9]{3}-[A-PR-Y0-9]{4}$', re.IGNORECASE) @@ -406,28 +407,35 @@ class IsAPowerOf(object): if val != int(val): raise ValidationError, gettext("This value must be a power of %s.") % self.power_of -class IsValidFloat(object): +class IsValidDecimal(object): def __init__(self, max_digits, decimal_places): self.max_digits, self.decimal_places = max_digits, decimal_places def __call__(self, field_data, all_data): - data = str(field_data) - try: - float(data) - except ValueError: + match = decimal_re.search(str(field_data)) + if not match: raise ValidationError, gettext("Please enter a valid decimal number.") - # Negative floats require more space to input. - max_allowed_length = data.startswith('-') and (self.max_digits + 2) or (self.max_digits + 1) - if len(data) > max_allowed_length: + + digits = len(match.group('digits') or '') + decimals = len(match.group('decimals') or '') + + if digits + decimals > self.max_digits: raise ValidationError, ngettext("Please enter a valid decimal number with at most %s total digit.", "Please enter a valid decimal number with at most %s total digits.", self.max_digits) % self.max_digits - if (not '.' in data and len(data) > (max_allowed_length - self.decimal_places - 1)) or ('.' in data and len(data) > (max_allowed_length - (self.decimal_places - len(data.split('.')[1])))): + if digits > (self.max_digits - self.decimal_places): raise ValidationError, ngettext( "Please enter a valid decimal number with a whole part of at most %s digit.", "Please enter a valid decimal number with a whole part of at most %s digits.", str(self.max_digits-self.decimal_places)) % str(self.max_digits-self.decimal_places) - if '.' in data and len(data.split('.')[1]) > self.decimal_places: + if decimals > self.decimal_places: raise ValidationError, ngettext("Please enter a valid decimal number with at most %s decimal place.", "Please enter a valid decimal number with at most %s decimal places.", self.decimal_places) % self.decimal_places +def isValidFloat(field_data, all_data): + data = str(field_data) + try: + float(data) + except ValueError: + raise ValidationError, gettext("Please enter a valid floating point number.") + class HasAllowableSize(object): """ Checks that the file-upload field data is a certain size. min_size and diff --git a/django/db/backends/ado_mssql/creation.py b/django/db/backends/ado_mssql/creation.py index 5158ba02f9..a1098ea43e 100644 --- a/django/db/backends/ado_mssql/creation.py +++ b/django/db/backends/ado_mssql/creation.py @@ -5,9 +5,10 @@ DATA_TYPES = { 'CommaSeparatedIntegerField': 'varchar(%(maxlength)s)', 'DateField': 'smalldatetime', 'DateTimeField': 'smalldatetime', + 'DecimalField': 'numeric(%(max_digits)s, %(decimal_places)s)', 'FileField': 'varchar(100)', 'FilePathField': 'varchar(100)', - 'FloatField': 'numeric(%(max_digits)s, %(decimal_places)s)', + 'FloatField': 'double precision', 'ImageField': 'varchar(100)', 'IntegerField': 'int', 'IPAddressField': 'char(15)', diff --git a/django/db/backends/mysql/base.py b/django/db/backends/mysql/base.py index 41f4638980..d4cb1fa964 100644 --- a/django/db/backends/mysql/base.py +++ b/django/db/backends/mysql/base.py @@ -15,7 +15,7 @@ except ImportError, e: # lexicographic ordering in this check because then (1, 2, 1, 'gamma') # inadvertently passes the version test. version = Database.version_info -if (version < (1,2,1) or (version[:3] == (1, 2, 1) and +if (version < (1,2,1) or (version[:3] == (1, 2, 1) and (len(version) < 5 or version[3] != 'final' or version[4] < 2))): raise ImportError, "MySQLdb-1.2.1p2 or newer is required; you have %s" % Database.__version__ @@ -36,6 +36,8 @@ IntegrityError = Database.IntegrityError django_conversions = conversions.copy() django_conversions.update({ FIELD_TYPE.TIME: util.typecast_time, + FIELD_TYPE.DECIMAL: util.typecast_decimal, + FIELD_TYPE.NEWDECIMAL: util.typecast_decimal, }) # This should match the numerical portion of the version numbers (we can treat diff --git a/django/db/backends/mysql/creation.py b/django/db/backends/mysql/creation.py index 22ed901653..1b23fbff6e 100644 --- a/django/db/backends/mysql/creation.py +++ b/django/db/backends/mysql/creation.py @@ -9,9 +9,10 @@ DATA_TYPES = { 'CommaSeparatedIntegerField': 'varchar(%(maxlength)s)', 'DateField': 'date', 'DateTimeField': 'datetime', + 'DecimalField': 'numeric(%(max_digits)s, %(decimal_places)s)', 'FileField': 'varchar(100)', 'FilePathField': 'varchar(100)', - 'FloatField': 'numeric(%(max_digits)s, %(decimal_places)s)', + 'FloatField': 'double precision', 'ImageField': 'varchar(100)', 'IntegerField': 'integer', 'IPAddressField': 'char(15)', diff --git a/django/db/backends/mysql/introspection.py b/django/db/backends/mysql/introspection.py index 558fe49787..39733311c5 100644 --- a/django/db/backends/mysql/introspection.py +++ b/django/db/backends/mysql/introspection.py @@ -76,7 +76,7 @@ def get_indexes(cursor, table_name): DATA_TYPES_REVERSE = { FIELD_TYPE.BLOB: 'TextField', FIELD_TYPE.CHAR: 'CharField', - FIELD_TYPE.DECIMAL: 'FloatField', + FIELD_TYPE.DECIMAL: 'DecimalField', FIELD_TYPE.DATE: 'DateField', FIELD_TYPE.DATETIME: 'DateTimeField', FIELD_TYPE.DOUBLE: 'FloatField', diff --git a/django/db/backends/mysql_old/base.py b/django/db/backends/mysql_old/base.py index d56b8513f9..4704fe80a5 100644 --- a/django/db/backends/mysql_old/base.py +++ b/django/db/backends/mysql_old/base.py @@ -24,6 +24,8 @@ django_conversions.update({ FIELD_TYPE.DATETIME: util.typecast_timestamp, FIELD_TYPE.DATE: util.typecast_date, FIELD_TYPE.TIME: util.typecast_time, + FIELD_TYPE.DECIMAL: util.typecast_decimal, + FIELD_TYPE.NEWDECIMAL: util.typecast_decimal, }) # This should match the numerical portion of the version numbers (we can treat diff --git a/django/db/backends/mysql_old/creation.py b/django/db/backends/mysql_old/creation.py index 22ed901653..1b23fbff6e 100644 --- a/django/db/backends/mysql_old/creation.py +++ b/django/db/backends/mysql_old/creation.py @@ -9,9 +9,10 @@ DATA_TYPES = { 'CommaSeparatedIntegerField': 'varchar(%(maxlength)s)', 'DateField': 'date', 'DateTimeField': 'datetime', + 'DecimalField': 'numeric(%(max_digits)s, %(decimal_places)s)', 'FileField': 'varchar(100)', 'FilePathField': 'varchar(100)', - 'FloatField': 'numeric(%(max_digits)s, %(decimal_places)s)', + 'FloatField': 'double precision', 'ImageField': 'varchar(100)', 'IntegerField': 'integer', 'IPAddressField': 'char(15)', diff --git a/django/db/backends/mysql_old/introspection.py b/django/db/backends/mysql_old/introspection.py index 5ea626a5a9..cb5b8320d9 100644 --- a/django/db/backends/mysql_old/introspection.py +++ b/django/db/backends/mysql_old/introspection.py @@ -76,7 +76,7 @@ def get_indexes(cursor, table_name): DATA_TYPES_REVERSE = { FIELD_TYPE.BLOB: 'TextField', FIELD_TYPE.CHAR: 'CharField', - FIELD_TYPE.DECIMAL: 'FloatField', + FIELD_TYPE.DECIMAL: 'DecimalField', FIELD_TYPE.DATE: 'DateField', FIELD_TYPE.DATETIME: 'DateTimeField', FIELD_TYPE.DOUBLE: 'FloatField', diff --git a/django/db/backends/oracle/creation.py b/django/db/backends/oracle/creation.py index da65df172e..14a864ac28 100644 --- a/django/db/backends/oracle/creation.py +++ b/django/db/backends/oracle/creation.py @@ -5,9 +5,10 @@ DATA_TYPES = { 'CommaSeparatedIntegerField': 'varchar2(%(maxlength)s)', 'DateField': 'date', 'DateTimeField': 'date', + 'DecimalField': 'number(%(max_digits)s, %(decimal_places)s)', 'FileField': 'varchar2(100)', 'FilePathField': 'varchar2(100)', - 'FloatField': 'number(%(max_digits)s, %(decimal_places)s)', + 'FloatField': 'double precision', 'ImageField': 'varchar2(100)', 'IntegerField': 'integer', 'IPAddressField': 'char(15)', diff --git a/django/db/backends/oracle/introspection.py b/django/db/backends/oracle/introspection.py index ecc8f372a8..7634206178 100644 --- a/django/db/backends/oracle/introspection.py +++ b/django/db/backends/oracle/introspection.py @@ -46,5 +46,5 @@ DATA_TYPES_REVERSE = { 1114: 'DateTimeField', 1184: 'DateTimeField', 1266: 'TimeField', - 1700: 'FloatField', + 1700: 'DecimalField', } diff --git a/django/db/backends/postgresql/base.py b/django/db/backends/postgresql/base.py index 1ae16feb25..a5b38a883d 100644 --- a/django/db/backends/postgresql/base.py +++ b/django/db/backends/postgresql/base.py @@ -249,6 +249,7 @@ except AttributeError: Database.register_type(Database.new_type((1083,1266), "TIME", util.typecast_time)) Database.register_type(Database.new_type((1114,1184), "TIMESTAMP", util.typecast_timestamp)) Database.register_type(Database.new_type((16,), "BOOLEAN", util.typecast_boolean)) +Database.register_type(Database.new_type((1700,), "NUMERIC", util.typecast_decimal)) OPERATOR_MAPPING = { 'exact': '= %s', diff --git a/django/db/backends/postgresql/creation.py b/django/db/backends/postgresql/creation.py index 6c130f368e..4646b68ab8 100644 --- a/django/db/backends/postgresql/creation.py +++ b/django/db/backends/postgresql/creation.py @@ -9,9 +9,10 @@ DATA_TYPES = { 'CommaSeparatedIntegerField': 'varchar(%(maxlength)s)', 'DateField': 'date', 'DateTimeField': 'timestamp with time zone', + 'DecimalField': 'numeric(%(max_digits)s, %(decimal_places)s)', 'FileField': 'varchar(100)', 'FilePathField': 'varchar(100)', - 'FloatField': 'numeric(%(max_digits)s, %(decimal_places)s)', + 'FloatField': 'double precision', 'ImageField': 'varchar(100)', 'IntegerField': 'integer', 'IPAddressField': 'inet', diff --git a/django/db/backends/postgresql/introspection.py b/django/db/backends/postgresql/introspection.py index 6e1d60c4ff..2605490afd 100644 --- a/django/db/backends/postgresql/introspection.py +++ b/django/db/backends/postgresql/introspection.py @@ -72,6 +72,7 @@ DATA_TYPES_REVERSE = { 21: 'SmallIntegerField', 23: 'IntegerField', 25: 'TextField', + 701: 'FloatField', 869: 'IPAddressField', 1043: 'CharField', 1082: 'DateField', @@ -79,5 +80,5 @@ DATA_TYPES_REVERSE = { 1114: 'DateTimeField', 1184: 'DateTimeField', 1266: 'TimeField', - 1700: 'FloatField', + 1700: 'DecimalField', } diff --git a/django/db/backends/postgresql_psycopg2/introspection.py b/django/db/backends/postgresql_psycopg2/introspection.py index a546da8c45..aa45fe7db7 100644 --- a/django/db/backends/postgresql_psycopg2/introspection.py +++ b/django/db/backends/postgresql_psycopg2/introspection.py @@ -72,6 +72,7 @@ DATA_TYPES_REVERSE = { 21: 'SmallIntegerField', 23: 'IntegerField', 25: 'TextField', + 701: 'FloatField', 869: 'IPAddressField', 1043: 'CharField', 1082: 'DateField', @@ -79,5 +80,5 @@ DATA_TYPES_REVERSE = { 1114: 'DateTimeField', 1184: 'DateTimeField', 1266: 'TimeField', - 1700: 'FloatField', + 1700: 'DecimalField', } diff --git a/django/db/backends/sqlite3/base.py b/django/db/backends/sqlite3/base.py index d8e1336a9a..5cd67a32f5 100644 --- a/django/db/backends/sqlite3/base.py +++ b/django/db/backends/sqlite3/base.py @@ -17,6 +17,11 @@ except ImportError, e: module = 'sqlite3' raise ImproperlyConfigured, "Error loading %s module: %s" % (module, e) +try: + import decimal +except ImportError: + from django.utils import _decimal as decimal # for Python 2.3 + DatabaseError = Database.DatabaseError IntegrityError = Database.IntegrityError @@ -26,6 +31,8 @@ Database.register_converter("date", util.typecast_date) Database.register_converter("datetime", util.typecast_timestamp) Database.register_converter("timestamp", util.typecast_timestamp) Database.register_converter("TIMESTAMP", util.typecast_timestamp) +Database.register_converter("decimal", util.typecast_decimal) +Database.register_adapter(decimal.Decimal, util.rev_typecast_decimal) def utf8rowFactory(cursor, row): def utf8(s): diff --git a/django/db/backends/sqlite3/creation.py b/django/db/backends/sqlite3/creation.py index 77f570b2e8..e63046ab7d 100644 --- a/django/db/backends/sqlite3/creation.py +++ b/django/db/backends/sqlite3/creation.py @@ -8,9 +8,10 @@ DATA_TYPES = { 'CommaSeparatedIntegerField': 'varchar(%(maxlength)s)', 'DateField': 'date', 'DateTimeField': 'datetime', + 'DecimalField': 'decimal', 'FileField': 'varchar(100)', 'FilePathField': 'varchar(100)', - 'FloatField': 'numeric(%(max_digits)s, %(decimal_places)s)', + 'FloatField': 'real', 'ImageField': 'varchar(100)', 'IntegerField': 'integer', 'IPAddressField': 'char(15)', diff --git a/django/db/backends/util.py b/django/db/backends/util.py index d14a337ca2..18f120b600 100644 --- a/django/db/backends/util.py +++ b/django/db/backends/util.py @@ -1,6 +1,11 @@ import datetime from time import time +try: + import decimal +except ImportError: + from django.utils import _decimal as decimal # for Python 2.3 + class CursorDebugWrapper(object): def __init__(self, cursor, db): self.cursor = cursor @@ -85,6 +90,11 @@ def typecast_boolean(s): if not s: return False return str(s)[0].lower() == 't' +def typecast_decimal(s): + if s is None: + return None + return decimal.Decimal(s) + ############################################### # Converters from Python to database (string) # ############################################### @@ -92,6 +102,11 @@ def typecast_boolean(s): def rev_typecast_boolean(obj, d): return obj and '1' or '0' +def rev_typecast_decimal(d): + if d is None: + return None + return str(d) + ################################################################################## # Helper functions for dictfetch* for databases that don't natively support them # ################################################################################## diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py index ba2e362f3a..136ce31b8b 100644 --- a/django/db/models/fields/__init__.py +++ b/django/db/models/fields/__init__.py @@ -10,6 +10,10 @@ from django.utils.itercompat import tee from django.utils.text import capfirst from django.utils.translation import gettext, gettext_lazy import datetime, os, time +try: + import decimal +except ImportError: + from django.utils import _decimal as decimal # for Python 2.3 class NOT_PROVIDED: pass @@ -573,6 +577,65 @@ class DateTimeField(DateField): defaults.update(kwargs) return super(DateTimeField, self).formfield(**defaults) +class DecimalField(Field): + empty_strings_allowed = False + def __init__(self, verbose_name=None, name=None, max_digits=None, decimal_places=None, **kwargs): + self.max_digits, self.decimal_places = max_digits, decimal_places + Field.__init__(self, verbose_name, name, **kwargs) + + def to_python(self, value): + if value is None: + return value + try: + return decimal.Decimal(value) + except decimal.InvalidOperation: + raise validators.ValidationError, gettext("This value must be a decimal number.") + + def _format(self, value): + if isinstance(value, basestring): + return value + else: + return self.format_number(value) + + def format_number(self, value): + """ + Formats a number into a string with the requisite number of digits and + decimal places. + """ + num_chars = self.max_digits + # Allow for a decimal point + if self.decimal_places > 0: + num_chars += 1 + # Allow for a minus sign + if value < 0: + num_chars += 1 + + return "%.*f" % (self.decimal_places, value) + + def get_db_prep_save(self, value): + if value is not None: + value = self._format(value) + return super(DecimalField, self).get_db_prep_save(value) + + def get_db_prep_lookup(self, lookup_type, value): + if lookup_type == 'range': + value = [self._format(v) for v in value] + else: + value = self._format(value) + return super(DecimalField, self).get_db_prep_lookup(lookup_type, value) + + def get_manipulator_field_objs(self): + return [curry(oldforms.DecimalField, max_digits=self.max_digits, decimal_places=self.decimal_places)] + + def formfield(self, **kwargs): + defaults = { + 'max_digits': self.max_digits, + 'decimal_places': self.decimal_places, + 'form_class': forms.DecimalField, + } + defaults.update(kwargs) + return super(DecimalField, self).formfield(**defaults) + class EmailField(CharField): def __init__(self, *args, **kwargs): kwargs['maxlength'] = 75 @@ -683,12 +746,14 @@ class FilePathField(Field): class FloatField(Field): empty_strings_allowed = False - def __init__(self, verbose_name=None, name=None, max_digits=None, decimal_places=None, **kwargs): - self.max_digits, self.decimal_places = max_digits, decimal_places - Field.__init__(self, verbose_name, name, **kwargs) def get_manipulator_field_objs(self): - return [curry(oldforms.FloatField, max_digits=self.max_digits, decimal_places=self.decimal_places)] + return [oldforms.FloatField] + + def formfield(self, **kwargs): + defaults = {'form_class': forms.FloatField} + defaults.update(kwargs) + return super(FloatField, self).formfield(**defaults) class ImageField(FileField): def __init__(self, verbose_name=None, name=None, width_field=None, height_field=None, **kwargs): diff --git a/django/newforms/fields.py b/django/newforms/fields.py index 30c675c14a..b73dd181e6 100644 --- a/django/newforms/fields.py +++ b/django/newforms/fields.py @@ -19,7 +19,7 @@ __all__ = ( 'DEFAULT_DATETIME_INPUT_FORMATS', 'DateTimeField', 'RegexField', 'EmailField', 'URLField', 'BooleanField', 'ChoiceField', 'NullBooleanField', 'MultipleChoiceField', - 'ComboField', 'MultiValueField', + 'ComboField', 'MultiValueField', 'FloatField', 'DecimalField', 'SplitDateTimeField', ) @@ -31,6 +31,11 @@ try: except NameError: from sets import Set as set # Python 2.3 fallback +try: + from decimal import Decimal +except ImportError: + from django.utils._decimal import Decimal # Python 2.3 fallback + class Field(object): widget = TextInput # Default widget to use when rendering this type of Field. hidden_widget = HiddenInput # Default widget to use when rendering this as "hidden". @@ -134,6 +139,67 @@ class IntegerField(Field): raise ValidationError(gettext(u'Ensure this value is greater than or equal to %s.') % self.min_value) return value +class FloatField(Field): + def __init__(self, max_value=None, min_value=None, *args, **kwargs): + self.max_value, self.min_value = max_value, min_value + Field.__init__(self, *args, **kwargs) + + def clean(self, value): + """ + Validates that float() can be called on the input. Returns a float. + Returns None for empty values. + """ + super(FloatField, self).clean(value) + if not self.required and value in EMPTY_VALUES: + return None + try: + value = float(value) + except (ValueError, TypeError): + raise ValidationError(gettext('Enter a number.')) + if self.max_value is not None and value > self.max_value: + raise ValidationError(gettext('Ensure this value is less than or equal to %s.') % self.max_value) + if self.min_value is not None and value < self.min_value: + raise ValidationError(gettext('Ensure this value is greater than or equal to %s.') % self.min_value) + return value + +decimal_re = re.compile(r'^-?(?P\d+)(\.(?P\d+))?$') + +class DecimalField(Field): + def __init__(self, max_value=None, min_value=None, max_digits=None, decimal_places=None, *args, **kwargs): + self.max_value, self.min_value = max_value, min_value + self.max_digits, self.decimal_places = max_digits, decimal_places + Field.__init__(self, *args, **kwargs) + + def clean(self, value): + """ + Validates that the input is a decimal number. Returns a Decimal + instance. Returns None for empty values. Ensures that there are no more + than max_digits in the number, and no more than decimal_places digits + after the decimal point. + """ + super(DecimalField, self).clean(value) + if not self.required and value in EMPTY_VALUES: + return None + value = value.strip() + match = decimal_re.search(value) + if not match: + raise ValidationError(gettext('Enter a number.')) + else: + value = Decimal(value) + digits = len(match.group('digits') or '') + decimals = len(match.group('decimals') or '') + if self.max_value is not None and value > self.max_value: + raise ValidationError(gettext('Ensure this value is less than or equal to %s.') % self.max_value) + if self.min_value is not None and value < self.min_value: + raise ValidationError(gettext('Ensure this value is greater than or equal to %s.') % self.min_value) + if self.max_digits is not None and (digits + decimals) > self.max_digits: + raise ValidationError(gettext('Ensure that there are no more than %s digits in total.') % self.max_digits) + if self.decimal_places is not None and decimals > self.decimal_places: + raise ValidationError(gettext('Ensure that there are no more than %s decimal places.') % self.decimal_places) + if self.max_digits is not None and self.decimal_places is not None and digits > (self.max_digits - self.decimal_places): + raise ValidationError(gettext('Ensure that there are no more than %s digits before the decimal point.') % (self.max_digits - self.decimal_places)) + return value + DEFAULT_DATE_INPUT_FORMATS = ( '%Y-%m-%d', '%m/%d/%Y', '%m/%d/%y', # '2006-10-25', '10/25/2006', '10/25/06' '%b %d %Y', '%b %d, %Y', # 'Oct 25 2006', 'Oct 25, 2006' diff --git a/django/oldforms/__init__.py b/django/oldforms/__init__.py index 0a4676ee8f..eed73ab156 100644 --- a/django/oldforms/__init__.py +++ b/django/oldforms/__init__.py @@ -750,14 +750,27 @@ class PositiveSmallIntegerField(IntegerField): raise validators.CriticalValidationError, gettext("Enter a whole number between 0 and 32,767.") class FloatField(TextField): + def __init__(self, field_name, is_required=False, validator_list=None): + if validator_list is None: validator_list = [] + validator_list = [validators.isValidFloat] + validator_list + TextField.__init__(self, field_name, is_required=is_required, validator_list=validator_list) + + def html2python(data): + if data == '' or data is None: + return None + return float(data) + html2python = staticmethod(html2python) + +class DecimalField(TextField): def __init__(self, field_name, max_digits, decimal_places, is_required=False, validator_list=None): if validator_list is None: validator_list = [] self.max_digits, self.decimal_places = max_digits, decimal_places - validator_list = [self.isValidFloat] + validator_list - TextField.__init__(self, field_name, max_digits+2, max_digits+2, is_required, validator_list) + validator_list = [self.isValidDecimal] + validator_list + # Initialise the TextField, making sure it's large enough to fit the number with a - sign and a decimal point. + super(DecimalField, self).__init__(field_name, max_digits+2, max_digits+2, is_required, validator_list) - def isValidFloat(self, field_data, all_data): - v = validators.IsValidFloat(self.max_digits, self.decimal_places) + def isValidDecimal(self, field_data, all_data): + v = validators.IsValidDecimal(self.max_digits, self.decimal_places) try: v(field_data, all_data) except validators.ValidationError, e: @@ -766,7 +779,14 @@ class FloatField(TextField): def html2python(data): if data == '' or data is None: return None - return float(data) + try: + import decimal + except ImportError: + from django.utils import decimal + try: + return decimal.Decimal(data) + except decimal.InvalidOperation, e: + raise ValueError, e html2python = staticmethod(html2python) #################### diff --git a/django/utils/_decimal.py b/django/utils/_decimal.py new file mode 100644 index 0000000000..677d26bb32 --- /dev/null +++ b/django/utils/_decimal.py @@ -0,0 +1,3079 @@ +# Copyright (c) 2004 Python Software Foundation. +# All rights reserved. + +# Written by Eric Price +# and Facundo Batista +# and Raymond Hettinger +# and Aahz +# and Tim Peters + +# This module is currently Py2.3 compatible and should be kept that way +# unless a major compelling advantage arises. IOW, 2.3 compatibility is +# strongly preferred, but not guaranteed. + +# Also, this module should be kept in sync with the latest updates of +# the IBM specification as it evolves. Those updates will be treated +# as bug fixes (deviation from the spec is a compatibility, usability +# bug) and will be backported. At this point the spec is stabilizing +# and the updates are becoming fewer, smaller, and less significant. + +""" +This is a Py2.3 implementation of decimal floating point arithmetic based on +the General Decimal Arithmetic Specification: + + www2.hursley.ibm.com/decimal/decarith.html + +and IEEE standard 854-1987: + + www.cs.berkeley.edu/~ejr/projects/754/private/drafts/854-1987/dir.html + +Decimal floating point has finite precision with arbitrarily large bounds. + +The purpose of the module is to support arithmetic using familiar +"schoolhouse" rules and to avoid the some of tricky representation +issues associated with binary floating point. The package is especially +useful for financial applications or for contexts where users have +expectations that are at odds with binary floating point (for instance, +in binary floating point, 1.00 % 0.1 gives 0.09999999999999995 instead +of the expected Decimal("0.00") returned by decimal floating point). + +Here are some examples of using the decimal module: + +>>> from decimal import * +>>> setcontext(ExtendedContext) +>>> Decimal(0) +Decimal("0") +>>> Decimal("1") +Decimal("1") +>>> Decimal("-.0123") +Decimal("-0.0123") +>>> Decimal(123456) +Decimal("123456") +>>> Decimal("123.45e12345678901234567890") +Decimal("1.2345E+12345678901234567892") +>>> Decimal("1.33") + Decimal("1.27") +Decimal("2.60") +>>> Decimal("12.34") + Decimal("3.87") - Decimal("18.41") +Decimal("-2.20") +>>> dig = Decimal(1) +>>> print dig / Decimal(3) +0.333333333 +>>> getcontext().prec = 18 +>>> print dig / Decimal(3) +0.333333333333333333 +>>> print dig.sqrt() +1 +>>> print Decimal(3).sqrt() +1.73205080756887729 +>>> print Decimal(3) ** 123 +4.85192780976896427E+58 +>>> inf = Decimal(1) / Decimal(0) +>>> print inf +Infinity +>>> neginf = Decimal(-1) / Decimal(0) +>>> print neginf +-Infinity +>>> print neginf + inf +NaN +>>> print neginf * inf +-Infinity +>>> print dig / 0 +Infinity +>>> getcontext().traps[DivisionByZero] = 1 +>>> print dig / 0 +Traceback (most recent call last): + ... + ... + ... +DivisionByZero: x / 0 +>>> c = Context() +>>> c.traps[InvalidOperation] = 0 +>>> print c.flags[InvalidOperation] +0 +>>> c.divide(Decimal(0), Decimal(0)) +Decimal("NaN") +>>> c.traps[InvalidOperation] = 1 +>>> print c.flags[InvalidOperation] +1 +>>> c.flags[InvalidOperation] = 0 +>>> print c.flags[InvalidOperation] +0 +>>> print c.divide(Decimal(0), Decimal(0)) +Traceback (most recent call last): + ... + ... + ... +InvalidOperation: 0 / 0 +>>> print c.flags[InvalidOperation] +1 +>>> c.flags[InvalidOperation] = 0 +>>> c.traps[InvalidOperation] = 0 +>>> print c.divide(Decimal(0), Decimal(0)) +NaN +>>> print c.flags[InvalidOperation] +1 +>>> +""" + +__all__ = [ + # Two major classes + 'Decimal', 'Context', + + # Contexts + 'DefaultContext', 'BasicContext', 'ExtendedContext', + + # Exceptions + 'DecimalException', 'Clamped', 'InvalidOperation', 'DivisionByZero', + 'Inexact', 'Rounded', 'Subnormal', 'Overflow', 'Underflow', + + # Constants for use in setting up contexts + 'ROUND_DOWN', 'ROUND_HALF_UP', 'ROUND_HALF_EVEN', 'ROUND_CEILING', + 'ROUND_FLOOR', 'ROUND_UP', 'ROUND_HALF_DOWN', + + # Functions for manipulating contexts + 'setcontext', 'getcontext' +] + +import copy as _copy + +#Rounding +ROUND_DOWN = 'ROUND_DOWN' +ROUND_HALF_UP = 'ROUND_HALF_UP' +ROUND_HALF_EVEN = 'ROUND_HALF_EVEN' +ROUND_CEILING = 'ROUND_CEILING' +ROUND_FLOOR = 'ROUND_FLOOR' +ROUND_UP = 'ROUND_UP' +ROUND_HALF_DOWN = 'ROUND_HALF_DOWN' + +#Rounding decision (not part of the public API) +NEVER_ROUND = 'NEVER_ROUND' # Round in division (non-divmod), sqrt ONLY +ALWAYS_ROUND = 'ALWAYS_ROUND' # Every operation rounds at end. + +#Errors + +class DecimalException(ArithmeticError): + """Base exception class. + + Used exceptions derive from this. + If an exception derives from another exception besides this (such as + Underflow (Inexact, Rounded, Subnormal) that indicates that it is only + called if the others are present. This isn't actually used for + anything, though. + + handle -- Called when context._raise_error is called and the + trap_enabler is set. First argument is self, second is the + context. More arguments can be given, those being after + the explanation in _raise_error (For example, + context._raise_error(NewError, '(-x)!', self._sign) would + call NewError().handle(context, self._sign).) + + To define a new exception, it should be sufficient to have it derive + from DecimalException. + """ + def handle(self, context, *args): + pass + + +class Clamped(DecimalException): + """Exponent of a 0 changed to fit bounds. + + This occurs and signals clamped if the exponent of a result has been + altered in order to fit the constraints of a specific concrete + representation. This may occur when the exponent of a zero result would + be outside the bounds of a representation, or when a large normal + number would have an encoded exponent that cannot be represented. In + this latter case, the exponent is reduced to fit and the corresponding + number of zero digits are appended to the coefficient ("fold-down"). + """ + + +class InvalidOperation(DecimalException): + """An invalid operation was performed. + + Various bad things cause this: + + Something creates a signaling NaN + -INF + INF + 0 * (+-)INF + (+-)INF / (+-)INF + x % 0 + (+-)INF % x + x._rescale( non-integer ) + sqrt(-x) , x > 0 + 0 ** 0 + x ** (non-integer) + x ** (+-)INF + An operand is invalid + """ + def handle(self, context, *args): + if args: + if args[0] == 1: #sNaN, must drop 's' but keep diagnostics + return Decimal( (args[1]._sign, args[1]._int, 'n') ) + return NaN + +class ConversionSyntax(InvalidOperation): + """Trying to convert badly formed string. + + This occurs and signals invalid-operation if an string is being + converted to a number and it does not conform to the numeric string + syntax. The result is [0,qNaN]. + """ + + def handle(self, context, *args): + return (0, (0,), 'n') #Passed to something which uses a tuple. + +class DivisionByZero(DecimalException, ZeroDivisionError): + """Division by 0. + + This occurs and signals division-by-zero if division of a finite number + by zero was attempted (during a divide-integer or divide operation, or a + power operation with negative right-hand operand), and the dividend was + not zero. + + The result of the operation is [sign,inf], where sign is the exclusive + or of the signs of the operands for divide, or is 1 for an odd power of + -0, for power. + """ + + def handle(self, context, sign, double = None, *args): + if double is not None: + return (Infsign[sign],)*2 + return Infsign[sign] + +class DivisionImpossible(InvalidOperation): + """Cannot perform the division adequately. + + This occurs and signals invalid-operation if the integer result of a + divide-integer or remainder operation had too many digits (would be + longer than precision). The result is [0,qNaN]. + """ + + def handle(self, context, *args): + return (NaN, NaN) + +class DivisionUndefined(InvalidOperation, ZeroDivisionError): + """Undefined result of division. + + This occurs and signals invalid-operation if division by zero was + attempted (during a divide-integer, divide, or remainder operation), and + the dividend is also zero. The result is [0,qNaN]. + """ + + def handle(self, context, tup=None, *args): + if tup is not None: + return (NaN, NaN) #for 0 %0, 0 // 0 + return NaN + +class Inexact(DecimalException): + """Had to round, losing information. + + This occurs and signals inexact whenever the result of an operation is + not exact (that is, it needed to be rounded and any discarded digits + were non-zero), or if an overflow or underflow condition occurs. The + result in all cases is unchanged. + + The inexact signal may be tested (or trapped) to determine if a given + operation (or sequence of operations) was inexact. + """ + pass + +class InvalidContext(InvalidOperation): + """Invalid context. Unknown rounding, for example. + + This occurs and signals invalid-operation if an invalid context was + detected during an operation. This can occur if contexts are not checked + on creation and either the precision exceeds the capability of the + underlying concrete representation or an unknown or unsupported rounding + was specified. These aspects of the context need only be checked when + the values are required to be used. The result is [0,qNaN]. + """ + + def handle(self, context, *args): + return NaN + +class Rounded(DecimalException): + """Number got rounded (not necessarily changed during rounding). + + This occurs and signals rounded whenever the result of an operation is + rounded (that is, some zero or non-zero digits were discarded from the + coefficient), or if an overflow or underflow condition occurs. The + result in all cases is unchanged. + + The rounded signal may be tested (or trapped) to determine if a given + operation (or sequence of operations) caused a loss of precision. + """ + pass + +class Subnormal(DecimalException): + """Exponent < Emin before rounding. + + This occurs and signals subnormal whenever the result of a conversion or + operation is subnormal (that is, its adjusted exponent is less than + Emin, before any rounding). The result in all cases is unchanged. + + The subnormal signal may be tested (or trapped) to determine if a given + or operation (or sequence of operations) yielded a subnormal result. + """ + pass + +class Overflow(Inexact, Rounded): + """Numerical overflow. + + This occurs and signals overflow if the adjusted exponent of a result + (from a conversion or from an operation that is not an attempt to divide + by zero), after rounding, would be greater than the largest value that + can be handled by the implementation (the value Emax). + + The result depends on the rounding mode: + + For round-half-up and round-half-even (and for round-half-down and + round-up, if implemented), the result of the operation is [sign,inf], + where sign is the sign of the intermediate result. For round-down, the + result is the largest finite number that can be represented in the + current precision, with the sign of the intermediate result. For + round-ceiling, the result is the same as for round-down if the sign of + the intermediate result is 1, or is [0,inf] otherwise. For round-floor, + the result is the same as for round-down if the sign of the intermediate + result is 0, or is [1,inf] otherwise. In all cases, Inexact and Rounded + will also be raised. + """ + + def handle(self, context, sign, *args): + if context.rounding in (ROUND_HALF_UP, ROUND_HALF_EVEN, + ROUND_HALF_DOWN, ROUND_UP): + return Infsign[sign] + if sign == 0: + if context.rounding == ROUND_CEILING: + return Infsign[sign] + return Decimal((sign, (9,)*context.prec, + context.Emax-context.prec+1)) + if sign == 1: + if context.rounding == ROUND_FLOOR: + return Infsign[sign] + return Decimal( (sign, (9,)*context.prec, + context.Emax-context.prec+1)) + + +class Underflow(Inexact, Rounded, Subnormal): + """Numerical underflow with result rounded to 0. + + This occurs and signals underflow if a result is inexact and the + adjusted exponent of the result would be smaller (more negative) than + the smallest value that can be handled by the implementation (the value + Emin). That is, the result is both inexact and subnormal. + + The result after an underflow will be a subnormal number rounded, if + necessary, so that its exponent is not less than Etiny. This may result + in 0 with the sign of the intermediate result and an exponent of Etiny. + + In all cases, Inexact, Rounded, and Subnormal will also be raised. + """ + +# List of public traps and flags +_signals = [Clamped, DivisionByZero, Inexact, Overflow, Rounded, + Underflow, InvalidOperation, Subnormal] + +# Map conditions (per the spec) to signals +_condition_map = {ConversionSyntax:InvalidOperation, + DivisionImpossible:InvalidOperation, + DivisionUndefined:InvalidOperation, + InvalidContext:InvalidOperation} + +##### Context Functions ####################################### + +# The getcontext() and setcontext() function manage access to a thread-local +# current context. Py2.4 offers direct support for thread locals. If that +# is not available, use threading.currentThread() which is slower but will +# work for older Pythons. If threads are not part of the build, create a +# mock threading object with threading.local() returning the module namespace. + +try: + import threading +except ImportError: + # Python was compiled without threads; create a mock object instead + import sys + class MockThreading: + def local(self, sys=sys): + return sys.modules[__name__] + threading = MockThreading() + del sys, MockThreading + +try: + threading.local + +except AttributeError: + + #To fix reloading, force it to create a new context + #Old contexts have different exceptions in their dicts, making problems. + if hasattr(threading.currentThread(), '__decimal_context__'): + del threading.currentThread().__decimal_context__ + + def setcontext(context): + """Set this thread's context to context.""" + if context in (DefaultContext, BasicContext, ExtendedContext): + context = context.copy() + context.clear_flags() + threading.currentThread().__decimal_context__ = context + + def getcontext(): + """Returns this thread's context. + + If this thread does not yet have a context, returns + a new context and sets this thread's context. + New contexts are copies of DefaultContext. + """ + try: + return threading.currentThread().__decimal_context__ + except AttributeError: + context = Context() + threading.currentThread().__decimal_context__ = context + return context + +else: + + local = threading.local() + if hasattr(local, '__decimal_context__'): + del local.__decimal_context__ + + def getcontext(_local=local): + """Returns this thread's context. + + If this thread does not yet have a context, returns + a new context and sets this thread's context. + New contexts are copies of DefaultContext. + """ + try: + return _local.__decimal_context__ + except AttributeError: + context = Context() + _local.__decimal_context__ = context + return context + + def setcontext(context, _local=local): + """Set this thread's context to context.""" + if context in (DefaultContext, BasicContext, ExtendedContext): + context = context.copy() + context.clear_flags() + _local.__decimal_context__ = context + + del threading, local # Don't contaminate the namespace + + +##### Decimal class ########################################### + +class Decimal(object): + """Floating point class for decimal arithmetic.""" + + __slots__ = ('_exp','_int','_sign', '_is_special') + # Generally, the value of the Decimal instance is given by + # (-1)**_sign * _int * 10**_exp + # Special values are signified by _is_special == True + + # We're immutable, so use __new__ not __init__ + def __new__(cls, value="0", context=None): + """Create a decimal point instance. + + >>> Decimal('3.14') # string input + Decimal("3.14") + >>> Decimal((0, (3, 1, 4), -2)) # tuple input (sign, digit_tuple, exponent) + Decimal("3.14") + >>> Decimal(314) # int or long + Decimal("314") + >>> Decimal(Decimal(314)) # another decimal instance + Decimal("314") + """ + + self = object.__new__(cls) + self._is_special = False + + # From an internal working value + if isinstance(value, _WorkRep): + self._sign = value.sign + self._int = tuple(map(int, str(value.int))) + self._exp = int(value.exp) + return self + + # From another decimal + if isinstance(value, Decimal): + self._exp = value._exp + self._sign = value._sign + self._int = value._int + self._is_special = value._is_special + return self + + # From an integer + if isinstance(value, (int,long)): + if value >= 0: + self._sign = 0 + else: + self._sign = 1 + self._exp = 0 + self._int = tuple(map(int, str(abs(value)))) + return self + + # tuple/list conversion (possibly from as_tuple()) + if isinstance(value, (list,tuple)): + if len(value) != 3: + raise ValueError, 'Invalid arguments' + if value[0] not in (0,1): + raise ValueError, 'Invalid sign' + for digit in value[1]: + if not isinstance(digit, (int,long)) or digit < 0: + raise ValueError, "The second value in the tuple must be composed of non negative integer elements." + + self._sign = value[0] + self._int = tuple(value[1]) + if value[2] in ('F','n','N'): + self._exp = value[2] + self._is_special = True + else: + self._exp = int(value[2]) + return self + + if isinstance(value, float): + raise TypeError("Cannot convert float to Decimal. " + + "First convert the float to a string") + + # Other argument types may require the context during interpretation + if context is None: + context = getcontext() + + # From a string + # REs insist on real strings, so we can too. + if isinstance(value, basestring): + if _isinfinity(value): + self._exp = 'F' + self._int = (0,) + self._is_special = True + if _isinfinity(value) == 1: + self._sign = 0 + else: + self._sign = 1 + return self + if _isnan(value): + sig, sign, diag = _isnan(value) + self._is_special = True + if len(diag) > context.prec: #Diagnostic info too long + self._sign, self._int, self._exp = \ + context._raise_error(ConversionSyntax) + return self + if sig == 1: + self._exp = 'n' #qNaN + else: #sig == 2 + self._exp = 'N' #sNaN + self._sign = sign + self._int = tuple(map(int, diag)) #Diagnostic info + return self + try: + self._sign, self._int, self._exp = _string2exact(value) + except ValueError: + self._is_special = True + self._sign, self._int, self._exp = context._raise_error(ConversionSyntax) + return self + + raise TypeError("Cannot convert %r to Decimal" % value) + + def _isnan(self): + """Returns whether the number is not actually one. + + 0 if a number + 1 if NaN + 2 if sNaN + """ + if self._is_special: + exp = self._exp + if exp == 'n': + return 1 + elif exp == 'N': + return 2 + return 0 + + def _isinfinity(self): + """Returns whether the number is infinite + + 0 if finite or not a number + 1 if +INF + -1 if -INF + """ + if self._exp == 'F': + if self._sign: + return -1 + return 1 + return 0 + + def _check_nans(self, other = None, context=None): + """Returns whether the number is not actually one. + + if self, other are sNaN, signal + if self, other are NaN return nan + return 0 + + Done before operations. + """ + + self_is_nan = self._isnan() + if other is None: + other_is_nan = False + else: + other_is_nan = other._isnan() + + if self_is_nan or other_is_nan: + if context is None: + context = getcontext() + + if self_is_nan == 2: + return context._raise_error(InvalidOperation, 'sNaN', + 1, self) + if other_is_nan == 2: + return context._raise_error(InvalidOperation, 'sNaN', + 1, other) + if self_is_nan: + return self + + return other + return 0 + + def __nonzero__(self): + """Is the number non-zero? + + 0 if self == 0 + 1 if self != 0 + """ + if self._is_special: + return 1 + return sum(self._int) != 0 + + def __cmp__(self, other, context=None): + other = _convert_other(other) + if other is NotImplemented: + return other + + if self._is_special or other._is_special: + ans = self._check_nans(other, context) + if ans: + return 1 # Comparison involving NaN's always reports self > other + + # INF = INF + return cmp(self._isinfinity(), other._isinfinity()) + + if not self and not other: + return 0 #If both 0, sign comparison isn't certain. + + #If different signs, neg one is less + if other._sign < self._sign: + return -1 + if self._sign < other._sign: + return 1 + + self_adjusted = self.adjusted() + other_adjusted = other.adjusted() + if self_adjusted == other_adjusted and \ + self._int + (0,)*(self._exp - other._exp) == \ + other._int + (0,)*(other._exp - self._exp): + return 0 #equal, except in precision. ([0]*(-x) = []) + elif self_adjusted > other_adjusted and self._int[0] != 0: + return (-1)**self._sign + elif self_adjusted < other_adjusted and other._int[0] != 0: + return -((-1)**self._sign) + + # Need to round, so make sure we have a valid context + if context is None: + context = getcontext() + + context = context._shallow_copy() + rounding = context._set_rounding(ROUND_UP) #round away from 0 + + flags = context._ignore_all_flags() + res = self.__sub__(other, context=context) + + context._regard_flags(*flags) + + context.rounding = rounding + + if not res: + return 0 + elif res._sign: + return -1 + return 1 + + def __eq__(self, other): + if not isinstance(other, (Decimal, int, long)): + return NotImplemented + return self.__cmp__(other) == 0 + + def __ne__(self, other): + if not isinstance(other, (Decimal, int, long)): + return NotImplemented + return self.__cmp__(other) != 0 + + def compare(self, other, context=None): + """Compares one to another. + + -1 => a < b + 0 => a = b + 1 => a > b + NaN => one is NaN + Like __cmp__, but returns Decimal instances. + """ + other = _convert_other(other) + if other is NotImplemented: + return other + + #compare(NaN, NaN) = NaN + if (self._is_special or other and other._is_special): + ans = self._check_nans(other, context) + if ans: + return ans + + return Decimal(self.__cmp__(other, context)) + + def __hash__(self): + """x.__hash__() <==> hash(x)""" + # Decimal integers must hash the same as the ints + # Non-integer decimals are normalized and hashed as strings + # Normalization assures that hast(100E-1) == hash(10) + if self._is_special: + if self._isnan(): + raise TypeError('Cannot hash a NaN value.') + return hash(str(self)) + i = int(self) + if self == Decimal(i): + return hash(i) + assert self.__nonzero__() # '-0' handled by integer case + return hash(str(self.normalize())) + + def as_tuple(self): + """Represents the number as a triple tuple. + + To show the internals exactly as they are. + """ + return (self._sign, self._int, self._exp) + + def __repr__(self): + """Represents the number as an instance of Decimal.""" + # Invariant: eval(repr(d)) == d + return 'Decimal("%s")' % str(self) + + def __str__(self, eng = 0, context=None): + """Return string representation of the number in scientific notation. + + Captures all of the information in the underlying representation. + """ + + if self._is_special: + if self._isnan(): + minus = '-'*self._sign + if self._int == (0,): + info = '' + else: + info = ''.join(map(str, self._int)) + if self._isnan() == 2: + return minus + 'sNaN' + info + return minus + 'NaN' + info + if self._isinfinity(): + minus = '-'*self._sign + return minus + 'Infinity' + + if context is None: + context = getcontext() + + tmp = map(str, self._int) + numdigits = len(self._int) + leftdigits = self._exp + numdigits + if eng and not self: #self = 0eX wants 0[.0[0]]eY, not [[0]0]0eY + if self._exp < 0 and self._exp >= -6: #short, no need for e/E + s = '-'*self._sign + '0.' + '0'*(abs(self._exp)) + return s + #exp is closest mult. of 3 >= self._exp + exp = ((self._exp - 1)// 3 + 1) * 3 + if exp != self._exp: + s = '0.'+'0'*(exp - self._exp) + else: + s = '0' + if exp != 0: + if context.capitals: + s += 'E' + else: + s += 'e' + if exp > 0: + s += '+' #0.0e+3, not 0.0e3 + s += str(exp) + s = '-'*self._sign + s + return s + if eng: + dotplace = (leftdigits-1)%3+1 + adjexp = leftdigits -1 - (leftdigits-1)%3 + else: + adjexp = leftdigits-1 + dotplace = 1 + if self._exp == 0: + pass + elif self._exp < 0 and adjexp >= 0: + tmp.insert(leftdigits, '.') + elif self._exp < 0 and adjexp >= -6: + tmp[0:0] = ['0'] * int(-leftdigits) + tmp.insert(0, '0.') + else: + if numdigits > dotplace: + tmp.insert(dotplace, '.') + elif numdigits < dotplace: + tmp.extend(['0']*(dotplace-numdigits)) + if adjexp: + if not context.capitals: + tmp.append('e') + else: + tmp.append('E') + if adjexp > 0: + tmp.append('+') + tmp.append(str(adjexp)) + if eng: + while tmp[0:1] == ['0']: + tmp[0:1] = [] + if len(tmp) == 0 or tmp[0] == '.' or tmp[0].lower() == 'e': + tmp[0:0] = ['0'] + if self._sign: + tmp.insert(0, '-') + + return ''.join(tmp) + + def to_eng_string(self, context=None): + """Convert to engineering-type string. + + Engineering notation has an exponent which is a multiple of 3, so there + are up to 3 digits left of the decimal place. + + Same rules for when in exponential and when as a value as in __str__. + """ + return self.__str__(eng=1, context=context) + + def __neg__(self, context=None): + """Returns a copy with the sign switched. + + Rounds, if it has reason. + """ + if self._is_special: + ans = self._check_nans(context=context) + if ans: + return ans + + if not self: + # -Decimal('0') is Decimal('0'), not Decimal('-0') + sign = 0 + elif self._sign: + sign = 0 + else: + sign = 1 + + if context is None: + context = getcontext() + if context._rounding_decision == ALWAYS_ROUND: + return Decimal((sign, self._int, self._exp))._fix(context) + return Decimal( (sign, self._int, self._exp)) + + def __pos__(self, context=None): + """Returns a copy, unless it is a sNaN. + + Rounds the number (if more then precision digits) + """ + if self._is_special: + ans = self._check_nans(context=context) + if ans: + return ans + + sign = self._sign + if not self: + # + (-0) = 0 + sign = 0 + + if context is None: + context = getcontext() + + if context._rounding_decision == ALWAYS_ROUND: + ans = self._fix(context) + else: + ans = Decimal(self) + ans._sign = sign + return ans + + def __abs__(self, round=1, context=None): + """Returns the absolute value of self. + + If the second argument is 0, do not round. + """ + if self._is_special: + ans = self._check_nans(context=context) + if ans: + return ans + + if not round: + if context is None: + context = getcontext() + context = context._shallow_copy() + context._set_rounding_decision(NEVER_ROUND) + + if self._sign: + ans = self.__neg__(context=context) + else: + ans = self.__pos__(context=context) + + return ans + + def __add__(self, other, context=None): + """Returns self + other. + + -INF + INF (or the reverse) cause InvalidOperation errors. + """ + other = _convert_other(other) + if other is NotImplemented: + return other + + if context is None: + context = getcontext() + + if self._is_special or other._is_special: + ans = self._check_nans(other, context) + if ans: + return ans + + if self._isinfinity(): + #If both INF, same sign => same as both, opposite => error. + if self._sign != other._sign and other._isinfinity(): + return context._raise_error(InvalidOperation, '-INF + INF') + return Decimal(self) + if other._isinfinity(): + return Decimal(other) #Can't both be infinity here + + shouldround = context._rounding_decision == ALWAYS_ROUND + + exp = min(self._exp, other._exp) + negativezero = 0 + if context.rounding == ROUND_FLOOR and self._sign != other._sign: + #If the answer is 0, the sign should be negative, in this case. + negativezero = 1 + + if not self and not other: + sign = min(self._sign, other._sign) + if negativezero: + sign = 1 + return Decimal( (sign, (0,), exp)) + if not self: + exp = max(exp, other._exp - context.prec-1) + ans = other._rescale(exp, watchexp=0, context=context) + if shouldround: + ans = ans._fix(context) + return ans + if not other: + exp = max(exp, self._exp - context.prec-1) + ans = self._rescale(exp, watchexp=0, context=context) + if shouldround: + ans = ans._fix(context) + return ans + + op1 = _WorkRep(self) + op2 = _WorkRep(other) + op1, op2 = _normalize(op1, op2, shouldround, context.prec) + + result = _WorkRep() + if op1.sign != op2.sign: + # Equal and opposite + if op1.int == op2.int: + if exp < context.Etiny(): + exp = context.Etiny() + context._raise_error(Clamped) + return Decimal((negativezero, (0,), exp)) + if op1.int < op2.int: + op1, op2 = op2, op1 + #OK, now abs(op1) > abs(op2) + if op1.sign == 1: + result.sign = 1 + op1.sign, op2.sign = op2.sign, op1.sign + else: + result.sign = 0 + #So we know the sign, and op1 > 0. + elif op1.sign == 1: + result.sign = 1 + op1.sign, op2.sign = (0, 0) + else: + result.sign = 0 + #Now, op1 > abs(op2) > 0 + + if op2.sign == 0: + result.int = op1.int + op2.int + else: + result.int = op1.int - op2.int + + result.exp = op1.exp + ans = Decimal(result) + if shouldround: + ans = ans._fix(context) + return ans + + __radd__ = __add__ + + def __sub__(self, other, context=None): + """Return self + (-other)""" + other = _convert_other(other) + if other is NotImplemented: + return other + + if self._is_special or other._is_special: + ans = self._check_nans(other, context=context) + if ans: + return ans + + # -Decimal(0) = Decimal(0), which we don't want since + # (-0 - 0 = -0 + (-0) = -0, but -0 + 0 = 0.) + # so we change the sign directly to a copy + tmp = Decimal(other) + tmp._sign = 1-tmp._sign + + return self.__add__(tmp, context=context) + + def __rsub__(self, other, context=None): + """Return other + (-self)""" + other = _convert_other(other) + if other is NotImplemented: + return other + + tmp = Decimal(self) + tmp._sign = 1 - tmp._sign + return other.__add__(tmp, context=context) + + def _increment(self, round=1, context=None): + """Special case of add, adding 1eExponent + + Since it is common, (rounding, for example) this adds + (sign)*one E self._exp to the number more efficiently than add. + + For example: + Decimal('5.624e10')._increment() == Decimal('5.625e10') + """ + if self._is_special: + ans = self._check_nans(context=context) + if ans: + return ans + + return Decimal(self) # Must be infinite, and incrementing makes no difference + + L = list(self._int) + L[-1] += 1 + spot = len(L)-1 + while L[spot] == 10: + L[spot] = 0 + if spot == 0: + L[0:0] = [1] + break + L[spot-1] += 1 + spot -= 1 + ans = Decimal((self._sign, L, self._exp)) + + if context is None: + context = getcontext() + if round and context._rounding_decision == ALWAYS_ROUND: + ans = ans._fix(context) + return ans + + def __mul__(self, other, context=None): + """Return self * other. + + (+-) INF * 0 (or its reverse) raise InvalidOperation. + """ + other = _convert_other(other) + if other is NotImplemented: + return other + + if context is None: + context = getcontext() + + resultsign = self._sign ^ other._sign + + if self._is_special or other._is_special: + ans = self._check_nans(other, context) + if ans: + return ans + + if self._isinfinity(): + if not other: + return context._raise_error(InvalidOperation, '(+-)INF * 0') + return Infsign[resultsign] + + if other._isinfinity(): + if not self: + return context._raise_error(InvalidOperation, '0 * (+-)INF') + return Infsign[resultsign] + + resultexp = self._exp + other._exp + shouldround = context._rounding_decision == ALWAYS_ROUND + + # Special case for multiplying by zero + if not self or not other: + ans = Decimal((resultsign, (0,), resultexp)) + if shouldround: + #Fixing in case the exponent is out of bounds + ans = ans._fix(context) + return ans + + # Special case for multiplying by power of 10 + if self._int == (1,): + ans = Decimal((resultsign, other._int, resultexp)) + if shouldround: + ans = ans._fix(context) + return ans + if other._int == (1,): + ans = Decimal((resultsign, self._int, resultexp)) + if shouldround: + ans = ans._fix(context) + return ans + + op1 = _WorkRep(self) + op2 = _WorkRep(other) + + ans = Decimal( (resultsign, map(int, str(op1.int * op2.int)), resultexp)) + if shouldround: + ans = ans._fix(context) + + return ans + __rmul__ = __mul__ + + def __div__(self, other, context=None): + """Return self / other.""" + return self._divide(other, context=context) + __truediv__ = __div__ + + def _divide(self, other, divmod = 0, context=None): + """Return a / b, to context.prec precision. + + divmod: + 0 => true division + 1 => (a //b, a%b) + 2 => a //b + 3 => a%b + + Actually, if divmod is 2 or 3 a tuple is returned, but errors for + computing the other value are not raised. + """ + other = _convert_other(other) + if other is NotImplemented: + if divmod in (0, 1): + return NotImplemented + return (NotImplemented, NotImplemented) + + if context is None: + context = getcontext() + + sign = self._sign ^ other._sign + + if self._is_special or other._is_special: + ans = self._check_nans(other, context) + if ans: + if divmod: + return (ans, ans) + return ans + + if self._isinfinity() and other._isinfinity(): + if divmod: + return (context._raise_error(InvalidOperation, + '(+-)INF // (+-)INF'), + context._raise_error(InvalidOperation, + '(+-)INF % (+-)INF')) + return context._raise_error(InvalidOperation, '(+-)INF/(+-)INF') + + if self._isinfinity(): + if divmod == 1: + return (Infsign[sign], + context._raise_error(InvalidOperation, 'INF % x')) + elif divmod == 2: + return (Infsign[sign], NaN) + elif divmod == 3: + return (Infsign[sign], + context._raise_error(InvalidOperation, 'INF % x')) + return Infsign[sign] + + if other._isinfinity(): + if divmod: + return (Decimal((sign, (0,), 0)), Decimal(self)) + context._raise_error(Clamped, 'Division by infinity') + return Decimal((sign, (0,), context.Etiny())) + + # Special cases for zeroes + if not self and not other: + if divmod: + return context._raise_error(DivisionUndefined, '0 / 0', 1) + return context._raise_error(DivisionUndefined, '0 / 0') + + if not self: + if divmod: + otherside = Decimal(self) + otherside._exp = min(self._exp, other._exp) + return (Decimal((sign, (0,), 0)), otherside) + exp = self._exp - other._exp + if exp < context.Etiny(): + exp = context.Etiny() + context._raise_error(Clamped, '0e-x / y') + if exp > context.Emax: + exp = context.Emax + context._raise_error(Clamped, '0e+x / y') + return Decimal( (sign, (0,), exp) ) + + if not other: + if divmod: + return context._raise_error(DivisionByZero, 'divmod(x,0)', + sign, 1) + return context._raise_error(DivisionByZero, 'x / 0', sign) + + #OK, so neither = 0, INF or NaN + + shouldround = context._rounding_decision == ALWAYS_ROUND + + #If we're dividing into ints, and self < other, stop. + #self.__abs__(0) does not round. + if divmod and (self.__abs__(0, context) < other.__abs__(0, context)): + + if divmod == 1 or divmod == 3: + exp = min(self._exp, other._exp) + ans2 = self._rescale(exp, context=context, watchexp=0) + if shouldround: + ans2 = ans2._fix(context) + return (Decimal( (sign, (0,), 0) ), + ans2) + + elif divmod == 2: + #Don't round the mod part, if we don't need it. + return (Decimal( (sign, (0,), 0) ), Decimal(self)) + + op1 = _WorkRep(self) + op2 = _WorkRep(other) + op1, op2, adjust = _adjust_coefficients(op1, op2) + res = _WorkRep( (sign, 0, (op1.exp - op2.exp)) ) + if divmod and res.exp > context.prec + 1: + return context._raise_error(DivisionImpossible) + + prec_limit = 10 ** context.prec + while 1: + while op2.int <= op1.int: + res.int += 1 + op1.int -= op2.int + if res.exp == 0 and divmod: + if res.int >= prec_limit and shouldround: + return context._raise_error(DivisionImpossible) + otherside = Decimal(op1) + frozen = context._ignore_all_flags() + + exp = min(self._exp, other._exp) + otherside = otherside._rescale(exp, context=context, watchexp=0) + context._regard_flags(*frozen) + if shouldround: + otherside = otherside._fix(context) + return (Decimal(res), otherside) + + if op1.int == 0 and adjust >= 0 and not divmod: + break + if res.int >= prec_limit and shouldround: + if divmod: + return context._raise_error(DivisionImpossible) + shouldround=1 + # Really, the answer is a bit higher, so adding a one to + # the end will make sure the rounding is right. + if op1.int != 0: + res.int *= 10 + res.int += 1 + res.exp -= 1 + + break + res.int *= 10 + res.exp -= 1 + adjust += 1 + op1.int *= 10 + op1.exp -= 1 + + if res.exp == 0 and divmod and op2.int > op1.int: + #Solves an error in precision. Same as a previous block. + + if res.int >= prec_limit and shouldround: + return context._raise_error(DivisionImpossible) + otherside = Decimal(op1) + frozen = context._ignore_all_flags() + + exp = min(self._exp, other._exp) + otherside = otherside._rescale(exp, context=context) + + context._regard_flags(*frozen) + + return (Decimal(res), otherside) + + ans = Decimal(res) + if shouldround: + ans = ans._fix(context) + return ans + + def __rdiv__(self, other, context=None): + """Swaps self/other and returns __div__.""" + other = _convert_other(other) + if other is NotImplemented: + return other + return other.__div__(self, context=context) + __rtruediv__ = __rdiv__ + + def __divmod__(self, other, context=None): + """ + (self // other, self % other) + """ + return self._divide(other, 1, context) + + def __rdivmod__(self, other, context=None): + """Swaps self/other and returns __divmod__.""" + other = _convert_other(other) + if other is NotImplemented: + return other + return other.__divmod__(self, context=context) + + def __mod__(self, other, context=None): + """ + self % other + """ + other = _convert_other(other) + if other is NotImplemented: + return other + + if self._is_special or other._is_special: + ans = self._check_nans(other, context) + if ans: + return ans + + if self and not other: + return context._raise_error(InvalidOperation, 'x % 0') + + return self._divide(other, 3, context)[1] + + def __rmod__(self, other, context=None): + """Swaps self/other and returns __mod__.""" + other = _convert_other(other) + if other is NotImplemented: + return other + return other.__mod__(self, context=context) + + def remainder_near(self, other, context=None): + """ + Remainder nearest to 0- abs(remainder-near) <= other/2 + """ + other = _convert_other(other) + if other is NotImplemented: + return other + + if self._is_special or other._is_special: + ans = self._check_nans(other, context) + if ans: + return ans + if self and not other: + return context._raise_error(InvalidOperation, 'x % 0') + + if context is None: + context = getcontext() + # If DivisionImpossible causes an error, do not leave Rounded/Inexact + # ignored in the calling function. + context = context._shallow_copy() + flags = context._ignore_flags(Rounded, Inexact) + #keep DivisionImpossible flags + (side, r) = self.__divmod__(other, context=context) + + if r._isnan(): + context._regard_flags(*flags) + return r + + context = context._shallow_copy() + rounding = context._set_rounding_decision(NEVER_ROUND) + + if other._sign: + comparison = other.__div__(Decimal(-2), context=context) + else: + comparison = other.__div__(Decimal(2), context=context) + + context._set_rounding_decision(rounding) + context._regard_flags(*flags) + + s1, s2 = r._sign, comparison._sign + r._sign, comparison._sign = 0, 0 + + if r < comparison: + r._sign, comparison._sign = s1, s2 + #Get flags now + self.__divmod__(other, context=context) + return r._fix(context) + r._sign, comparison._sign = s1, s2 + + rounding = context._set_rounding_decision(NEVER_ROUND) + + (side, r) = self.__divmod__(other, context=context) + context._set_rounding_decision(rounding) + if r._isnan(): + return r + + decrease = not side._iseven() + rounding = context._set_rounding_decision(NEVER_ROUND) + side = side.__abs__(context=context) + context._set_rounding_decision(rounding) + + s1, s2 = r._sign, comparison._sign + r._sign, comparison._sign = 0, 0 + if r > comparison or decrease and r == comparison: + r._sign, comparison._sign = s1, s2 + context.prec += 1 + if len(side.__add__(Decimal(1), context=context)._int) >= context.prec: + context.prec -= 1 + return context._raise_error(DivisionImpossible)[1] + context.prec -= 1 + if self._sign == other._sign: + r = r.__sub__(other, context=context) + else: + r = r.__add__(other, context=context) + else: + r._sign, comparison._sign = s1, s2 + + return r._fix(context) + + def __floordiv__(self, other, context=None): + """self // other""" + return self._divide(other, 2, context)[0] + + def __rfloordiv__(self, other, context=None): + """Swaps self/other and returns __floordiv__.""" + other = _convert_other(other) + if other is NotImplemented: + return other + return other.__floordiv__(self, context=context) + + def __float__(self): + """Float representation.""" + return float(str(self)) + + def __int__(self): + """Converts self to an int, truncating if necessary.""" + if self._is_special: + if self._isnan(): + context = getcontext() + return context._raise_error(InvalidContext) + elif self._isinfinity(): + raise OverflowError, "Cannot convert infinity to long" + if self._exp >= 0: + s = ''.join(map(str, self._int)) + '0'*self._exp + else: + s = ''.join(map(str, self._int))[:self._exp] + if s == '': + s = '0' + sign = '-'*self._sign + return int(sign + s) + + def __long__(self): + """Converts to a long. + + Equivalent to long(int(self)) + """ + return long(self.__int__()) + + def _fix(self, context): + """Round if it is necessary to keep self within prec precision. + + Rounds and fixes the exponent. Does not raise on a sNaN. + + Arguments: + self - Decimal instance + context - context used. + """ + if self._is_special: + return self + if context is None: + context = getcontext() + prec = context.prec + ans = self._fixexponents(context) + if len(ans._int) > prec: + ans = ans._round(prec, context=context) + ans = ans._fixexponents(context) + return ans + + def _fixexponents(self, context): + """Fix the exponents and return a copy with the exponent in bounds. + Only call if known to not be a special value. + """ + folddown = context._clamp + Emin = context.Emin + ans = self + ans_adjusted = ans.adjusted() + if ans_adjusted < Emin: + Etiny = context.Etiny() + if ans._exp < Etiny: + if not ans: + ans = Decimal(self) + ans._exp = Etiny + context._raise_error(Clamped) + return ans + ans = ans._rescale(Etiny, context=context) + #It isn't zero, and exp < Emin => subnormal + context._raise_error(Subnormal) + if context.flags[Inexact]: + context._raise_error(Underflow) + else: + if ans: + #Only raise subnormal if non-zero. + context._raise_error(Subnormal) + else: + Etop = context.Etop() + if folddown and ans._exp > Etop: + context._raise_error(Clamped) + ans = ans._rescale(Etop, context=context) + else: + Emax = context.Emax + if ans_adjusted > Emax: + if not ans: + ans = Decimal(self) + ans._exp = Emax + context._raise_error(Clamped) + return ans + context._raise_error(Inexact) + context._raise_error(Rounded) + return context._raise_error(Overflow, 'above Emax', ans._sign) + return ans + + def _round(self, prec=None, rounding=None, context=None): + """Returns a rounded version of self. + + You can specify the precision or rounding method. Otherwise, the + context determines it. + """ + + if self._is_special: + ans = self._check_nans(context=context) + if ans: + return ans + + if self._isinfinity(): + return Decimal(self) + + if context is None: + context = getcontext() + + if rounding is None: + rounding = context.rounding + if prec is None: + prec = context.prec + + if not self: + if prec <= 0: + dig = (0,) + exp = len(self._int) - prec + self._exp + else: + dig = (0,) * prec + exp = len(self._int) + self._exp - prec + ans = Decimal((self._sign, dig, exp)) + context._raise_error(Rounded) + return ans + + if prec == 0: + temp = Decimal(self) + temp._int = (0,)+temp._int + prec = 1 + elif prec < 0: + exp = self._exp + len(self._int) - prec - 1 + temp = Decimal( (self._sign, (0, 1), exp)) + prec = 1 + else: + temp = Decimal(self) + + numdigits = len(temp._int) + if prec == numdigits: + return temp + + # See if we need to extend precision + expdiff = prec - numdigits + if expdiff > 0: + tmp = list(temp._int) + tmp.extend([0] * expdiff) + ans = Decimal( (temp._sign, tmp, temp._exp - expdiff)) + return ans + + #OK, but maybe all the lost digits are 0. + lostdigits = self._int[expdiff:] + if lostdigits == (0,) * len(lostdigits): + ans = Decimal( (temp._sign, temp._int[:prec], temp._exp - expdiff)) + #Rounded, but not Inexact + context._raise_error(Rounded) + return ans + + # Okay, let's round and lose data + + this_function = getattr(temp, self._pick_rounding_function[rounding]) + #Now we've got the rounding function + + if prec != context.prec: + context = context._shallow_copy() + context.prec = prec + ans = this_function(prec, expdiff, context) + context._raise_error(Rounded) + context._raise_error(Inexact, 'Changed in rounding') + + return ans + + _pick_rounding_function = {} + + def _round_down(self, prec, expdiff, context): + """Also known as round-towards-0, truncate.""" + return Decimal( (self._sign, self._int[:prec], self._exp - expdiff) ) + + def _round_half_up(self, prec, expdiff, context, tmp = None): + """Rounds 5 up (away from 0)""" + + if tmp is None: + tmp = Decimal( (self._sign,self._int[:prec], self._exp - expdiff)) + if self._int[prec] >= 5: + tmp = tmp._increment(round=0, context=context) + if len(tmp._int) > prec: + return Decimal( (tmp._sign, tmp._int[:-1], tmp._exp + 1)) + return tmp + + def _round_half_even(self, prec, expdiff, context): + """Round 5 to even, rest to nearest.""" + + tmp = Decimal( (self._sign, self._int[:prec], self._exp - expdiff)) + half = (self._int[prec] == 5) + if half: + for digit in self._int[prec+1:]: + if digit != 0: + half = 0 + break + if half: + if self._int[prec-1] & 1 == 0: + return tmp + return self._round_half_up(prec, expdiff, context, tmp) + + def _round_half_down(self, prec, expdiff, context): + """Round 5 down""" + + tmp = Decimal( (self._sign, self._int[:prec], self._exp - expdiff)) + half = (self._int[prec] == 5) + if half: + for digit in self._int[prec+1:]: + if digit != 0: + half = 0 + break + if half: + return tmp + return self._round_half_up(prec, expdiff, context, tmp) + + def _round_up(self, prec, expdiff, context): + """Rounds away from 0.""" + tmp = Decimal( (self._sign, self._int[:prec], self._exp - expdiff) ) + for digit in self._int[prec:]: + if digit != 0: + tmp = tmp._increment(round=1, context=context) + if len(tmp._int) > prec: + return Decimal( (tmp._sign, tmp._int[:-1], tmp._exp + 1)) + else: + return tmp + return tmp + + def _round_ceiling(self, prec, expdiff, context): + """Rounds up (not away from 0 if negative.)""" + if self._sign: + return self._round_down(prec, expdiff, context) + else: + return self._round_up(prec, expdiff, context) + + def _round_floor(self, prec, expdiff, context): + """Rounds down (not towards 0 if negative)""" + if not self._sign: + return self._round_down(prec, expdiff, context) + else: + return self._round_up(prec, expdiff, context) + + def __pow__(self, n, modulo = None, context=None): + """Return self ** n (mod modulo) + + If modulo is None (default), don't take it mod modulo. + """ + n = _convert_other(n) + if n is NotImplemented: + return n + + if context is None: + context = getcontext() + + if self._is_special or n._is_special or n.adjusted() > 8: + #Because the spot << doesn't work with really big exponents + if n._isinfinity() or n.adjusted() > 8: + return context._raise_error(InvalidOperation, 'x ** INF') + + ans = self._check_nans(n, context) + if ans: + return ans + + if not n._isinteger(): + return context._raise_error(InvalidOperation, 'x ** (non-integer)') + + if not self and not n: + return context._raise_error(InvalidOperation, '0 ** 0') + + if not n: + return Decimal(1) + + if self == Decimal(1): + return Decimal(1) + + sign = self._sign and not n._iseven() + n = int(n) + + if self._isinfinity(): + if modulo: + return context._raise_error(InvalidOperation, 'INF % x') + if n > 0: + return Infsign[sign] + return Decimal( (sign, (0,), 0) ) + + #with ludicrously large exponent, just raise an overflow and return inf. + if not modulo and n > 0 and (self._exp + len(self._int) - 1) * n > context.Emax \ + and self: + + tmp = Decimal('inf') + tmp._sign = sign + context._raise_error(Rounded) + context._raise_error(Inexact) + context._raise_error(Overflow, 'Big power', sign) + return tmp + + elength = len(str(abs(n))) + firstprec = context.prec + + if not modulo and firstprec + elength + 1 > DefaultContext.Emax: + return context._raise_error(Overflow, 'Too much precision.', sign) + + mul = Decimal(self) + val = Decimal(1) + context = context._shallow_copy() + context.prec = firstprec + elength + 1 + if n < 0: + #n is a long now, not Decimal instance + n = -n + mul = Decimal(1).__div__(mul, context=context) + + spot = 1 + while spot <= n: + spot <<= 1 + + spot >>= 1 + #Spot is the highest power of 2 less than n + while spot: + val = val.__mul__(val, context=context) + if val._isinfinity(): + val = Infsign[sign] + break + if spot & n: + val = val.__mul__(mul, context=context) + if modulo is not None: + val = val.__mod__(modulo, context=context) + spot >>= 1 + context.prec = firstprec + + if context._rounding_decision == ALWAYS_ROUND: + return val._fix(context) + return val + + def __rpow__(self, other, context=None): + """Swaps self/other and returns __pow__.""" + other = _convert_other(other) + if other is NotImplemented: + return other + return other.__pow__(self, context=context) + + def normalize(self, context=None): + """Normalize- strip trailing 0s, change anything equal to 0 to 0e0""" + + if self._is_special: + ans = self._check_nans(context=context) + if ans: + return ans + + dup = self._fix(context) + if dup._isinfinity(): + return dup + + if not dup: + return Decimal( (dup._sign, (0,), 0) ) + end = len(dup._int) + exp = dup._exp + while dup._int[end-1] == 0: + exp += 1 + end -= 1 + return Decimal( (dup._sign, dup._int[:end], exp) ) + + + def quantize(self, exp, rounding=None, context=None, watchexp=1): + """Quantize self so its exponent is the same as that of exp. + + Similar to self._rescale(exp._exp) but with error checking. + """ + if self._is_special or exp._is_special: + ans = self._check_nans(exp, context) + if ans: + return ans + + if exp._isinfinity() or self._isinfinity(): + if exp._isinfinity() and self._isinfinity(): + return self #if both are inf, it is OK + if context is None: + context = getcontext() + return context._raise_error(InvalidOperation, + 'quantize with one INF') + return self._rescale(exp._exp, rounding, context, watchexp) + + def same_quantum(self, other): + """Test whether self and other have the same exponent. + + same as self._exp == other._exp, except NaN == sNaN + """ + if self._is_special or other._is_special: + if self._isnan() or other._isnan(): + return self._isnan() and other._isnan() and True + if self._isinfinity() or other._isinfinity(): + return self._isinfinity() and other._isinfinity() and True + return self._exp == other._exp + + def _rescale(self, exp, rounding=None, context=None, watchexp=1): + """Rescales so that the exponent is exp. + + exp = exp to scale to (an integer) + rounding = rounding version + watchexp: if set (default) an error is returned if exp is greater + than Emax or less than Etiny. + """ + if context is None: + context = getcontext() + + if self._is_special: + if self._isinfinity(): + return context._raise_error(InvalidOperation, 'rescale with an INF') + + ans = self._check_nans(context=context) + if ans: + return ans + + if watchexp and (context.Emax < exp or context.Etiny() > exp): + return context._raise_error(InvalidOperation, 'rescale(a, INF)') + + if not self: + ans = Decimal(self) + ans._int = (0,) + ans._exp = exp + return ans + + diff = self._exp - exp + digits = len(self._int) + diff + + if watchexp and digits > context.prec: + return context._raise_error(InvalidOperation, 'Rescale > prec') + + tmp = Decimal(self) + tmp._int = (0,) + tmp._int + digits += 1 + + if digits < 0: + tmp._exp = -digits + tmp._exp + tmp._int = (0,1) + digits = 1 + tmp = tmp._round(digits, rounding, context=context) + + if tmp._int[0] == 0 and len(tmp._int) > 1: + tmp._int = tmp._int[1:] + tmp._exp = exp + + tmp_adjusted = tmp.adjusted() + if tmp and tmp_adjusted < context.Emin: + context._raise_error(Subnormal) + elif tmp and tmp_adjusted > context.Emax: + return context._raise_error(InvalidOperation, 'rescale(a, INF)') + return tmp + + def to_integral(self, rounding=None, context=None): + """Rounds to the nearest integer, without raising inexact, rounded.""" + if self._is_special: + ans = self._check_nans(context=context) + if ans: + return ans + if self._exp >= 0: + return self + if context is None: + context = getcontext() + flags = context._ignore_flags(Rounded, Inexact) + ans = self._rescale(0, rounding, context=context) + context._regard_flags(flags) + return ans + + def sqrt(self, context=None): + """Return the square root of self. + + Uses a converging algorithm (Xn+1 = 0.5*(Xn + self / Xn)) + Should quadratically approach the right answer. + """ + if self._is_special: + ans = self._check_nans(context=context) + if ans: + return ans + + if self._isinfinity() and self._sign == 0: + return Decimal(self) + + if not self: + #exponent = self._exp / 2, using round_down. + #if self._exp < 0: + # exp = (self._exp+1) // 2 + #else: + exp = (self._exp) // 2 + if self._sign == 1: + #sqrt(-0) = -0 + return Decimal( (1, (0,), exp)) + else: + return Decimal( (0, (0,), exp)) + + if context is None: + context = getcontext() + + if self._sign == 1: + return context._raise_error(InvalidOperation, 'sqrt(-x), x > 0') + + tmp = Decimal(self) + + expadd = tmp._exp // 2 + if tmp._exp & 1: + tmp._int += (0,) + tmp._exp = 0 + else: + tmp._exp = 0 + + context = context._shallow_copy() + flags = context._ignore_all_flags() + firstprec = context.prec + context.prec = 3 + if tmp.adjusted() & 1 == 0: + ans = Decimal( (0, (8,1,9), tmp.adjusted() - 2) ) + ans = ans.__add__(tmp.__mul__(Decimal((0, (2,5,9), -2)), + context=context), context=context) + ans._exp -= 1 + tmp.adjusted() // 2 + else: + ans = Decimal( (0, (2,5,9), tmp._exp + len(tmp._int)- 3) ) + ans = ans.__add__(tmp.__mul__(Decimal((0, (8,1,9), -3)), + context=context), context=context) + ans._exp -= 1 + tmp.adjusted() // 2 + + #ans is now a linear approximation. + + Emax, Emin = context.Emax, context.Emin + context.Emax, context.Emin = DefaultContext.Emax, DefaultContext.Emin + + half = Decimal('0.5') + + maxp = firstprec + 2 + rounding = context._set_rounding(ROUND_HALF_EVEN) + while 1: + context.prec = min(2*context.prec - 2, maxp) + ans = half.__mul__(ans.__add__(tmp.__div__(ans, context=context), + context=context), context=context) + if context.prec == maxp: + break + + #round to the answer's precision-- the only error can be 1 ulp. + context.prec = firstprec + prevexp = ans.adjusted() + ans = ans._round(context=context) + + #Now, check if the other last digits are better. + context.prec = firstprec + 1 + # In case we rounded up another digit and we should actually go lower. + if prevexp != ans.adjusted(): + ans._int += (0,) + ans._exp -= 1 + + + lower = ans.__sub__(Decimal((0, (5,), ans._exp-1)), context=context) + context._set_rounding(ROUND_UP) + if lower.__mul__(lower, context=context) > (tmp): + ans = ans.__sub__(Decimal((0, (1,), ans._exp)), context=context) + + else: + upper = ans.__add__(Decimal((0, (5,), ans._exp-1)),context=context) + context._set_rounding(ROUND_DOWN) + if upper.__mul__(upper, context=context) < tmp: + ans = ans.__add__(Decimal((0, (1,), ans._exp)),context=context) + + ans._exp += expadd + + context.prec = firstprec + context.rounding = rounding + ans = ans._fix(context) + + rounding = context._set_rounding_decision(NEVER_ROUND) + if not ans.__mul__(ans, context=context) == self: + # Only rounded/inexact if here. + context._regard_flags(flags) + context._raise_error(Rounded) + context._raise_error(Inexact) + else: + #Exact answer, so let's set the exponent right. + #if self._exp < 0: + # exp = (self._exp +1)// 2 + #else: + exp = self._exp // 2 + context.prec += ans._exp - exp + ans = ans._rescale(exp, context=context) + context.prec = firstprec + context._regard_flags(flags) + context.Emax, context.Emin = Emax, Emin + + return ans._fix(context) + + def max(self, other, context=None): + """Returns the larger value. + + like max(self, other) except if one is not a number, returns + NaN (and signals if one is sNaN). Also rounds. + """ + other = _convert_other(other) + if other is NotImplemented: + return other + + if self._is_special or other._is_special: + # if one operand is a quiet NaN and the other is number, then the + # number is always returned + sn = self._isnan() + on = other._isnan() + if sn or on: + if on == 1 and sn != 2: + return self + if sn == 1 and on != 2: + return other + return self._check_nans(other, context) + + ans = self + c = self.__cmp__(other) + if c == 0: + # if both operands are finite and equal in numerical value + # then an ordering is applied: + # + # if the signs differ then max returns the operand with the + # positive sign and min returns the operand with the negative sign + # + # if the signs are the same then the exponent is used to select + # the result. + if self._sign != other._sign: + if self._sign: + ans = other + elif self._exp < other._exp and not self._sign: + ans = other + elif self._exp > other._exp and self._sign: + ans = other + elif c == -1: + ans = other + + if context is None: + context = getcontext() + if context._rounding_decision == ALWAYS_ROUND: + return ans._fix(context) + return ans + + def min(self, other, context=None): + """Returns the smaller value. + + like min(self, other) except if one is not a number, returns + NaN (and signals if one is sNaN). Also rounds. + """ + other = _convert_other(other) + if other is NotImplemented: + return other + + if self._is_special or other._is_special: + # if one operand is a quiet NaN and the other is number, then the + # number is always returned + sn = self._isnan() + on = other._isnan() + if sn or on: + if on == 1 and sn != 2: + return self + if sn == 1 and on != 2: + return other + return self._check_nans(other, context) + + ans = self + c = self.__cmp__(other) + if c == 0: + # if both operands are finite and equal in numerical value + # then an ordering is applied: + # + # if the signs differ then max returns the operand with the + # positive sign and min returns the operand with the negative sign + # + # if the signs are the same then the exponent is used to select + # the result. + if self._sign != other._sign: + if other._sign: + ans = other + elif self._exp > other._exp and not self._sign: + ans = other + elif self._exp < other._exp and self._sign: + ans = other + elif c == 1: + ans = other + + if context is None: + context = getcontext() + if context._rounding_decision == ALWAYS_ROUND: + return ans._fix(context) + return ans + + def _isinteger(self): + """Returns whether self is an integer""" + if self._exp >= 0: + return True + rest = self._int[self._exp:] + return rest == (0,)*len(rest) + + def _iseven(self): + """Returns 1 if self is even. Assumes self is an integer.""" + if self._exp > 0: + return 1 + return self._int[-1+self._exp] & 1 == 0 + + def adjusted(self): + """Return the adjusted exponent of self""" + try: + return self._exp + len(self._int) - 1 + #If NaN or Infinity, self._exp is string + except TypeError: + return 0 + + # support for pickling, copy, and deepcopy + def __reduce__(self): + return (self.__class__, (str(self),)) + + def __copy__(self): + if type(self) == Decimal: + return self # I'm immutable; therefore I am my own clone + return self.__class__(str(self)) + + def __deepcopy__(self, memo): + if type(self) == Decimal: + return self # My components are also immutable + return self.__class__(str(self)) + +##### Context class ########################################### + + +# get rounding method function: +rounding_functions = [name for name in Decimal.__dict__.keys() if name.startswith('_round_')] +for name in rounding_functions: + #name is like _round_half_even, goes to the global ROUND_HALF_EVEN value. + globalname = name[1:].upper() + val = globals()[globalname] + Decimal._pick_rounding_function[val] = name + +del name, val, globalname, rounding_functions + +class Context(object): + """Contains the context for a Decimal instance. + + Contains: + prec - precision (for use in rounding, division, square roots..) + rounding - rounding type. (how you round) + _rounding_decision - ALWAYS_ROUND, NEVER_ROUND -- do you round? + traps - If traps[exception] = 1, then the exception is + raised when it is caused. Otherwise, a value is + substituted in. + flags - When an exception is caused, flags[exception] is incremented. + (Whether or not the trap_enabler is set) + Should be reset by user of Decimal instance. + Emin - Minimum exponent + Emax - Maximum exponent + capitals - If 1, 1*10^1 is printed as 1E+1. + If 0, printed as 1e1 + _clamp - If 1, change exponents if too high (Default 0) + """ + + def __init__(self, prec=None, rounding=None, + traps=None, flags=None, + _rounding_decision=None, + Emin=None, Emax=None, + capitals=None, _clamp=0, + _ignored_flags=None): + if flags is None: + flags = [] + if _ignored_flags is None: + _ignored_flags = [] + if not isinstance(flags, dict): + flags = dict([(s,s in flags) for s in _signals]) + del s + if traps is not None and not isinstance(traps, dict): + traps = dict([(s,s in traps) for s in _signals]) + del s + for name, val in locals().items(): + if val is None: + setattr(self, name, _copy.copy(getattr(DefaultContext, name))) + else: + setattr(self, name, val) + del self.self + + def __repr__(self): + """Show the current context.""" + s = [] + s.append('Context(prec=%(prec)d, rounding=%(rounding)s, Emin=%(Emin)d, Emax=%(Emax)d, capitals=%(capitals)d' % vars(self)) + s.append('flags=[' + ', '.join([f.__name__ for f, v in self.flags.items() if v]) + ']') + s.append('traps=[' + ', '.join([t.__name__ for t, v in self.traps.items() if v]) + ']') + return ', '.join(s) + ')' + + def clear_flags(self): + """Reset all flags to zero""" + for flag in self.flags: + self.flags[flag] = 0 + + def _shallow_copy(self): + """Returns a shallow copy from self.""" + nc = Context(self.prec, self.rounding, self.traps, self.flags, + self._rounding_decision, self.Emin, self.Emax, + self.capitals, self._clamp, self._ignored_flags) + return nc + + def copy(self): + """Returns a deep copy from self.""" + nc = Context(self.prec, self.rounding, self.traps.copy(), self.flags.copy(), + self._rounding_decision, self.Emin, self.Emax, + self.capitals, self._clamp, self._ignored_flags) + return nc + __copy__ = copy + + def _raise_error(self, condition, explanation = None, *args): + """Handles an error + + If the flag is in _ignored_flags, returns the default response. + Otherwise, it increments the flag, then, if the corresponding + trap_enabler is set, it reaises the exception. Otherwise, it returns + the default value after incrementing the flag. + """ + error = _condition_map.get(condition, condition) + if error in self._ignored_flags: + #Don't touch the flag + return error().handle(self, *args) + + self.flags[error] += 1 + if not self.traps[error]: + #The errors define how to handle themselves. + return condition().handle(self, *args) + + # Errors should only be risked on copies of the context + #self._ignored_flags = [] + raise error, explanation + + def _ignore_all_flags(self): + """Ignore all flags, if they are raised""" + return self._ignore_flags(*_signals) + + def _ignore_flags(self, *flags): + """Ignore the flags, if they are raised""" + # Do not mutate-- This way, copies of a context leave the original + # alone. + self._ignored_flags = (self._ignored_flags + list(flags)) + return list(flags) + + def _regard_flags(self, *flags): + """Stop ignoring the flags, if they are raised""" + if flags and isinstance(flags[0], (tuple,list)): + flags = flags[0] + for flag in flags: + self._ignored_flags.remove(flag) + + def __hash__(self): + """A Context cannot be hashed.""" + # We inherit object.__hash__, so we must deny this explicitly + raise TypeError, "Cannot hash a Context." + + def Etiny(self): + """Returns Etiny (= Emin - prec + 1)""" + return int(self.Emin - self.prec + 1) + + def Etop(self): + """Returns maximum exponent (= Emax - prec + 1)""" + return int(self.Emax - self.prec + 1) + + def _set_rounding_decision(self, type): + """Sets the rounding decision. + + Sets the rounding decision, and returns the current (previous) + rounding decision. Often used like: + + context = context._shallow_copy() + # That so you don't change the calling context + # if an error occurs in the middle (say DivisionImpossible is raised). + + rounding = context._set_rounding_decision(NEVER_ROUND) + instance = instance / Decimal(2) + context._set_rounding_decision(rounding) + + This will make it not round for that operation. + """ + + rounding = self._rounding_decision + self._rounding_decision = type + return rounding + + def _set_rounding(self, type): + """Sets the rounding type. + + Sets the rounding type, and returns the current (previous) + rounding type. Often used like: + + context = context.copy() + # so you don't change the calling context + # if an error occurs in the middle. + rounding = context._set_rounding(ROUND_UP) + val = self.__sub__(other, context=context) + context._set_rounding(rounding) + + This will make it round up for that operation. + """ + rounding = self.rounding + self.rounding= type + return rounding + + def create_decimal(self, num='0'): + """Creates a new Decimal instance but using self as context.""" + d = Decimal(num, context=self) + return d._fix(self) + + #Methods + def abs(self, a): + """Returns the absolute value of the operand. + + If the operand is negative, the result is the same as using the minus + operation on the operand. Otherwise, the result is the same as using + the plus operation on the operand. + + >>> ExtendedContext.abs(Decimal('2.1')) + Decimal("2.1") + >>> ExtendedContext.abs(Decimal('-100')) + Decimal("100") + >>> ExtendedContext.abs(Decimal('101.5')) + Decimal("101.5") + >>> ExtendedContext.abs(Decimal('-101.5')) + Decimal("101.5") + """ + return a.__abs__(context=self) + + def add(self, a, b): + """Return the sum of the two operands. + + >>> ExtendedContext.add(Decimal('12'), Decimal('7.00')) + Decimal("19.00") + >>> ExtendedContext.add(Decimal('1E+2'), Decimal('1.01E+4')) + Decimal("1.02E+4") + """ + return a.__add__(b, context=self) + + def _apply(self, a): + return str(a._fix(self)) + + def compare(self, a, b): + """Compares values numerically. + + If the signs of the operands differ, a value representing each operand + ('-1' if the operand is less than zero, '0' if the operand is zero or + negative zero, or '1' if the operand is greater than zero) is used in + place of that operand for the comparison instead of the actual + operand. + + The comparison is then effected by subtracting the second operand from + the first and then returning a value according to the result of the + subtraction: '-1' if the result is less than zero, '0' if the result is + zero or negative zero, or '1' if the result is greater than zero. + + >>> ExtendedContext.compare(Decimal('2.1'), Decimal('3')) + Decimal("-1") + >>> ExtendedContext.compare(Decimal('2.1'), Decimal('2.1')) + Decimal("0") + >>> ExtendedContext.compare(Decimal('2.1'), Decimal('2.10')) + Decimal("0") + >>> ExtendedContext.compare(Decimal('3'), Decimal('2.1')) + Decimal("1") + >>> ExtendedContext.compare(Decimal('2.1'), Decimal('-3')) + Decimal("1") + >>> ExtendedContext.compare(Decimal('-3'), Decimal('2.1')) + Decimal("-1") + """ + return a.compare(b, context=self) + + def divide(self, a, b): + """Decimal division in a specified context. + + >>> ExtendedContext.divide(Decimal('1'), Decimal('3')) + Decimal("0.333333333") + >>> ExtendedContext.divide(Decimal('2'), Decimal('3')) + Decimal("0.666666667") + >>> ExtendedContext.divide(Decimal('5'), Decimal('2')) + Decimal("2.5") + >>> ExtendedContext.divide(Decimal('1'), Decimal('10')) + Decimal("0.1") + >>> ExtendedContext.divide(Decimal('12'), Decimal('12')) + Decimal("1") + >>> ExtendedContext.divide(Decimal('8.00'), Decimal('2')) + Decimal("4.00") + >>> ExtendedContext.divide(Decimal('2.400'), Decimal('2.0')) + Decimal("1.20") + >>> ExtendedContext.divide(Decimal('1000'), Decimal('100')) + Decimal("10") + >>> ExtendedContext.divide(Decimal('1000'), Decimal('1')) + Decimal("1000") + >>> ExtendedContext.divide(Decimal('2.40E+6'), Decimal('2')) + Decimal("1.20E+6") + """ + return a.__div__(b, context=self) + + def divide_int(self, a, b): + """Divides two numbers and returns the integer part of the result. + + >>> ExtendedContext.divide_int(Decimal('2'), Decimal('3')) + Decimal("0") + >>> ExtendedContext.divide_int(Decimal('10'), Decimal('3')) + Decimal("3") + >>> ExtendedContext.divide_int(Decimal('1'), Decimal('0.3')) + Decimal("3") + """ + return a.__floordiv__(b, context=self) + + def divmod(self, a, b): + return a.__divmod__(b, context=self) + + def max(self, a,b): + """max compares two values numerically and returns the maximum. + + If either operand is a NaN then the general rules apply. + Otherwise, the operands are compared as as though by the compare + operation. If they are numerically equal then the left-hand operand + is chosen as the result. Otherwise the maximum (closer to positive + infinity) of the two operands is chosen as the result. + + >>> ExtendedContext.max(Decimal('3'), Decimal('2')) + Decimal("3") + >>> ExtendedContext.max(Decimal('-10'), Decimal('3')) + Decimal("3") + >>> ExtendedContext.max(Decimal('1.0'), Decimal('1')) + Decimal("1") + >>> ExtendedContext.max(Decimal('7'), Decimal('NaN')) + Decimal("7") + """ + return a.max(b, context=self) + + def min(self, a,b): + """min compares two values numerically and returns the minimum. + + If either operand is a NaN then the general rules apply. + Otherwise, the operands are compared as as though by the compare + operation. If they are numerically equal then the left-hand operand + is chosen as the result. Otherwise the minimum (closer to negative + infinity) of the two operands is chosen as the result. + + >>> ExtendedContext.min(Decimal('3'), Decimal('2')) + Decimal("2") + >>> ExtendedContext.min(Decimal('-10'), Decimal('3')) + Decimal("-10") + >>> ExtendedContext.min(Decimal('1.0'), Decimal('1')) + Decimal("1.0") + >>> ExtendedContext.min(Decimal('7'), Decimal('NaN')) + Decimal("7") + """ + return a.min(b, context=self) + + def minus(self, a): + """Minus corresponds to unary prefix minus in Python. + + The operation is evaluated using the same rules as subtract; the + operation minus(a) is calculated as subtract('0', a) where the '0' + has the same exponent as the operand. + + >>> ExtendedContext.minus(Decimal('1.3')) + Decimal("-1.3") + >>> ExtendedContext.minus(Decimal('-1.3')) + Decimal("1.3") + """ + return a.__neg__(context=self) + + def multiply(self, a, b): + """multiply multiplies two operands. + + If either operand is a special value then the general rules apply. + Otherwise, the operands are multiplied together ('long multiplication'), + resulting in a number which may be as long as the sum of the lengths + of the two operands. + + >>> ExtendedContext.multiply(Decimal('1.20'), Decimal('3')) + Decimal("3.60") + >>> ExtendedContext.multiply(Decimal('7'), Decimal('3')) + Decimal("21") + >>> ExtendedContext.multiply(Decimal('0.9'), Decimal('0.8')) + Decimal("0.72") + >>> ExtendedContext.multiply(Decimal('0.9'), Decimal('-0')) + Decimal("-0.0") + >>> ExtendedContext.multiply(Decimal('654321'), Decimal('654321')) + Decimal("4.28135971E+11") + """ + return a.__mul__(b, context=self) + + def normalize(self, a): + """normalize reduces an operand to its simplest form. + + Essentially a plus operation with all trailing zeros removed from the + result. + + >>> ExtendedContext.normalize(Decimal('2.1')) + Decimal("2.1") + >>> ExtendedContext.normalize(Decimal('-2.0')) + Decimal("-2") + >>> ExtendedContext.normalize(Decimal('1.200')) + Decimal("1.2") + >>> ExtendedContext.normalize(Decimal('-120')) + Decimal("-1.2E+2") + >>> ExtendedContext.normalize(Decimal('120.00')) + Decimal("1.2E+2") + >>> ExtendedContext.normalize(Decimal('0.00')) + Decimal("0") + """ + return a.normalize(context=self) + + def plus(self, a): + """Plus corresponds to unary prefix plus in Python. + + The operation is evaluated using the same rules as add; the + operation plus(a) is calculated as add('0', a) where the '0' + has the same exponent as the operand. + + >>> ExtendedContext.plus(Decimal('1.3')) + Decimal("1.3") + >>> ExtendedContext.plus(Decimal('-1.3')) + Decimal("-1.3") + """ + return a.__pos__(context=self) + + def power(self, a, b, modulo=None): + """Raises a to the power of b, to modulo if given. + + The right-hand operand must be a whole number whose integer part (after + any exponent has been applied) has no more than 9 digits and whose + fractional part (if any) is all zeros before any rounding. The operand + may be positive, negative, or zero; if negative, the absolute value of + the power is used, and the left-hand operand is inverted (divided into + 1) before use. + + If the increased precision needed for the intermediate calculations + exceeds the capabilities of the implementation then an Invalid operation + condition is raised. + + If, when raising to a negative power, an underflow occurs during the + division into 1, the operation is not halted at that point but + continues. + + >>> ExtendedContext.power(Decimal('2'), Decimal('3')) + Decimal("8") + >>> ExtendedContext.power(Decimal('2'), Decimal('-3')) + Decimal("0.125") + >>> ExtendedContext.power(Decimal('1.7'), Decimal('8')) + Decimal("69.7575744") + >>> ExtendedContext.power(Decimal('Infinity'), Decimal('-2')) + Decimal("0") + >>> ExtendedContext.power(Decimal('Infinity'), Decimal('-1')) + Decimal("0") + >>> ExtendedContext.power(Decimal('Infinity'), Decimal('0')) + Decimal("1") + >>> ExtendedContext.power(Decimal('Infinity'), Decimal('1')) + Decimal("Infinity") + >>> ExtendedContext.power(Decimal('Infinity'), Decimal('2')) + Decimal("Infinity") + >>> ExtendedContext.power(Decimal('-Infinity'), Decimal('-2')) + Decimal("0") + >>> ExtendedContext.power(Decimal('-Infinity'), Decimal('-1')) + Decimal("-0") + >>> ExtendedContext.power(Decimal('-Infinity'), Decimal('0')) + Decimal("1") + >>> ExtendedContext.power(Decimal('-Infinity'), Decimal('1')) + Decimal("-Infinity") + >>> ExtendedContext.power(Decimal('-Infinity'), Decimal('2')) + Decimal("Infinity") + >>> ExtendedContext.power(Decimal('0'), Decimal('0')) + Decimal("NaN") + """ + return a.__pow__(b, modulo, context=self) + + def quantize(self, a, b): + """Returns a value equal to 'a' (rounded) and having the exponent of 'b'. + + The coefficient of the result is derived from that of the left-hand + operand. It may be rounded using the current rounding setting (if the + exponent is being increased), multiplied by a positive power of ten (if + the exponent is being decreased), or is unchanged (if the exponent is + already equal to that of the right-hand operand). + + Unlike other operations, if the length of the coefficient after the + quantize operation would be greater than precision then an Invalid + operation condition is raised. This guarantees that, unless there is an + error condition, the exponent of the result of a quantize is always + equal to that of the right-hand operand. + + Also unlike other operations, quantize will never raise Underflow, even + if the result is subnormal and inexact. + + >>> ExtendedContext.quantize(Decimal('2.17'), Decimal('0.001')) + Decimal("2.170") + >>> ExtendedContext.quantize(Decimal('2.17'), Decimal('0.01')) + Decimal("2.17") + >>> ExtendedContext.quantize(Decimal('2.17'), Decimal('0.1')) + Decimal("2.2") + >>> ExtendedContext.quantize(Decimal('2.17'), Decimal('1e+0')) + Decimal("2") + >>> ExtendedContext.quantize(Decimal('2.17'), Decimal('1e+1')) + Decimal("0E+1") + >>> ExtendedContext.quantize(Decimal('-Inf'), Decimal('Infinity')) + Decimal("-Infinity") + >>> ExtendedContext.quantize(Decimal('2'), Decimal('Infinity')) + Decimal("NaN") + >>> ExtendedContext.quantize(Decimal('-0.1'), Decimal('1')) + Decimal("-0") + >>> ExtendedContext.quantize(Decimal('-0'), Decimal('1e+5')) + Decimal("-0E+5") + >>> ExtendedContext.quantize(Decimal('+35236450.6'), Decimal('1e-2')) + Decimal("NaN") + >>> ExtendedContext.quantize(Decimal('-35236450.6'), Decimal('1e-2')) + Decimal("NaN") + >>> ExtendedContext.quantize(Decimal('217'), Decimal('1e-1')) + Decimal("217.0") + >>> ExtendedContext.quantize(Decimal('217'), Decimal('1e-0')) + Decimal("217") + >>> ExtendedContext.quantize(Decimal('217'), Decimal('1e+1')) + Decimal("2.2E+2") + >>> ExtendedContext.quantize(Decimal('217'), Decimal('1e+2')) + Decimal("2E+2") + """ + return a.quantize(b, context=self) + + def remainder(self, a, b): + """Returns the remainder from integer division. + + The result is the residue of the dividend after the operation of + calculating integer division as described for divide-integer, rounded to + precision digits if necessary. The sign of the result, if non-zero, is + the same as that of the original dividend. + + This operation will fail under the same conditions as integer division + (that is, if integer division on the same two operands would fail, the + remainder cannot be calculated). + + >>> ExtendedContext.remainder(Decimal('2.1'), Decimal('3')) + Decimal("2.1") + >>> ExtendedContext.remainder(Decimal('10'), Decimal('3')) + Decimal("1") + >>> ExtendedContext.remainder(Decimal('-10'), Decimal('3')) + Decimal("-1") + >>> ExtendedContext.remainder(Decimal('10.2'), Decimal('1')) + Decimal("0.2") + >>> ExtendedContext.remainder(Decimal('10'), Decimal('0.3')) + Decimal("0.1") + >>> ExtendedContext.remainder(Decimal('3.6'), Decimal('1.3')) + Decimal("1.0") + """ + return a.__mod__(b, context=self) + + def remainder_near(self, a, b): + """Returns to be "a - b * n", where n is the integer nearest the exact + value of "x / b" (if two integers are equally near then the even one + is chosen). If the result is equal to 0 then its sign will be the + sign of a. + + This operation will fail under the same conditions as integer division + (that is, if integer division on the same two operands would fail, the + remainder cannot be calculated). + + >>> ExtendedContext.remainder_near(Decimal('2.1'), Decimal('3')) + Decimal("-0.9") + >>> ExtendedContext.remainder_near(Decimal('10'), Decimal('6')) + Decimal("-2") + >>> ExtendedContext.remainder_near(Decimal('10'), Decimal('3')) + Decimal("1") + >>> ExtendedContext.remainder_near(Decimal('-10'), Decimal('3')) + Decimal("-1") + >>> ExtendedContext.remainder_near(Decimal('10.2'), Decimal('1')) + Decimal("0.2") + >>> ExtendedContext.remainder_near(Decimal('10'), Decimal('0.3')) + Decimal("0.1") + >>> ExtendedContext.remainder_near(Decimal('3.6'), Decimal('1.3')) + Decimal("-0.3") + """ + return a.remainder_near(b, context=self) + + def same_quantum(self, a, b): + """Returns True if the two operands have the same exponent. + + The result is never affected by either the sign or the coefficient of + either operand. + + >>> ExtendedContext.same_quantum(Decimal('2.17'), Decimal('0.001')) + False + >>> ExtendedContext.same_quantum(Decimal('2.17'), Decimal('0.01')) + True + >>> ExtendedContext.same_quantum(Decimal('2.17'), Decimal('1')) + False + >>> ExtendedContext.same_quantum(Decimal('Inf'), Decimal('-Inf')) + True + """ + return a.same_quantum(b) + + def sqrt(self, a): + """Returns the square root of a non-negative number to context precision. + + If the result must be inexact, it is rounded using the round-half-even + algorithm. + + >>> ExtendedContext.sqrt(Decimal('0')) + Decimal("0") + >>> ExtendedContext.sqrt(Decimal('-0')) + Decimal("-0") + >>> ExtendedContext.sqrt(Decimal('0.39')) + Decimal("0.624499800") + >>> ExtendedContext.sqrt(Decimal('100')) + Decimal("10") + >>> ExtendedContext.sqrt(Decimal('1')) + Decimal("1") + >>> ExtendedContext.sqrt(Decimal('1.0')) + Decimal("1.0") + >>> ExtendedContext.sqrt(Decimal('1.00')) + Decimal("1.0") + >>> ExtendedContext.sqrt(Decimal('7')) + Decimal("2.64575131") + >>> ExtendedContext.sqrt(Decimal('10')) + Decimal("3.16227766") + >>> ExtendedContext.prec + 9 + """ + return a.sqrt(context=self) + + def subtract(self, a, b): + """Return the difference between the two operands. + + >>> ExtendedContext.subtract(Decimal('1.3'), Decimal('1.07')) + Decimal("0.23") + >>> ExtendedContext.subtract(Decimal('1.3'), Decimal('1.30')) + Decimal("0.00") + >>> ExtendedContext.subtract(Decimal('1.3'), Decimal('2.07')) + Decimal("-0.77") + """ + return a.__sub__(b, context=self) + + def to_eng_string(self, a): + """Converts a number to a string, using scientific notation. + + The operation is not affected by the context. + """ + return a.to_eng_string(context=self) + + def to_sci_string(self, a): + """Converts a number to a string, using scientific notation. + + The operation is not affected by the context. + """ + return a.__str__(context=self) + + def to_integral(self, a): + """Rounds to an integer. + + When the operand has a negative exponent, the result is the same + as using the quantize() operation using the given operand as the + left-hand-operand, 1E+0 as the right-hand-operand, and the precision + of the operand as the precision setting, except that no flags will + be set. The rounding mode is taken from the context. + + >>> ExtendedContext.to_integral(Decimal('2.1')) + Decimal("2") + >>> ExtendedContext.to_integral(Decimal('100')) + Decimal("100") + >>> ExtendedContext.to_integral(Decimal('100.0')) + Decimal("100") + >>> ExtendedContext.to_integral(Decimal('101.5')) + Decimal("102") + >>> ExtendedContext.to_integral(Decimal('-101.5')) + Decimal("-102") + >>> ExtendedContext.to_integral(Decimal('10E+5')) + Decimal("1.0E+6") + >>> ExtendedContext.to_integral(Decimal('7.89E+77')) + Decimal("7.89E+77") + >>> ExtendedContext.to_integral(Decimal('-Inf')) + Decimal("-Infinity") + """ + return a.to_integral(context=self) + +class _WorkRep(object): + __slots__ = ('sign','int','exp') + # sign: 0 or 1 + # int: int or long + # exp: None, int, or string + + def __init__(self, value=None): + if value is None: + self.sign = None + self.int = 0 + self.exp = None + elif isinstance(value, Decimal): + self.sign = value._sign + cum = 0 + for digit in value._int: + cum = cum * 10 + digit + self.int = cum + self.exp = value._exp + else: + # assert isinstance(value, tuple) + self.sign = value[0] + self.int = value[1] + self.exp = value[2] + + def __repr__(self): + return "(%r, %r, %r)" % (self.sign, self.int, self.exp) + + __str__ = __repr__ + + + +def _normalize(op1, op2, shouldround = 0, prec = 0): + """Normalizes op1, op2 to have the same exp and length of coefficient. + + Done during addition. + """ + # Yes, the exponent is a long, but the difference between exponents + # must be an int-- otherwise you'd get a big memory problem. + numdigits = int(op1.exp - op2.exp) + if numdigits < 0: + numdigits = -numdigits + tmp = op2 + other = op1 + else: + tmp = op1 + other = op2 + + + if shouldround and numdigits > prec + 1: + # Big difference in exponents - check the adjusted exponents + tmp_len = len(str(tmp.int)) + other_len = len(str(other.int)) + if numdigits > (other_len + prec + 1 - tmp_len): + # If the difference in adjusted exps is > prec+1, we know + # other is insignificant, so might as well put a 1 after the precision. + # (since this is only for addition.) Also stops use of massive longs. + + extend = prec + 2 - tmp_len + if extend <= 0: + extend = 1 + tmp.int *= 10 ** extend + tmp.exp -= extend + other.int = 1 + other.exp = tmp.exp + return op1, op2 + + tmp.int *= 10 ** numdigits + tmp.exp -= numdigits + return op1, op2 + +def _adjust_coefficients(op1, op2): + """Adjust op1, op2 so that op2.int * 10 > op1.int >= op2.int. + + Returns the adjusted op1, op2 as well as the change in op1.exp-op2.exp. + + Used on _WorkRep instances during division. + """ + adjust = 0 + #If op1 is smaller, make it larger + while op2.int > op1.int: + op1.int *= 10 + op1.exp -= 1 + adjust += 1 + + #If op2 is too small, make it larger + while op1.int >= (10 * op2.int): + op2.int *= 10 + op2.exp -= 1 + adjust -= 1 + + return op1, op2, adjust + +##### Helper Functions ######################################## + +def _convert_other(other): + """Convert other to Decimal. + + Verifies that it's ok to use in an implicit construction. + """ + if isinstance(other, Decimal): + return other + if isinstance(other, (int, long)): + return Decimal(other) + return NotImplemented + +_infinity_map = { + 'inf' : 1, + 'infinity' : 1, + '+inf' : 1, + '+infinity' : 1, + '-inf' : -1, + '-infinity' : -1 +} + +def _isinfinity(num): + """Determines whether a string or float is infinity. + + +1 for negative infinity; 0 for finite ; +1 for positive infinity + """ + num = str(num).lower() + return _infinity_map.get(num, 0) + +def _isnan(num): + """Determines whether a string or float is NaN + + (1, sign, diagnostic info as string) => NaN + (2, sign, diagnostic info as string) => sNaN + 0 => not a NaN + """ + num = str(num).lower() + if not num: + return 0 + + #get the sign, get rid of trailing [+-] + sign = 0 + if num[0] == '+': + num = num[1:] + elif num[0] == '-': #elif avoids '+-nan' + num = num[1:] + sign = 1 + + if num.startswith('nan'): + if len(num) > 3 and not num[3:].isdigit(): #diagnostic info + return 0 + return (1, sign, num[3:].lstrip('0')) + if num.startswith('snan'): + if len(num) > 4 and not num[4:].isdigit(): + return 0 + return (2, sign, num[4:].lstrip('0')) + return 0 + + +##### Setup Specific Contexts ################################ + +# The default context prototype used by Context() +# Is mutable, so that new contexts can have different default values + +DefaultContext = Context( + prec=28, rounding=ROUND_HALF_EVEN, + traps=[DivisionByZero, Overflow, InvalidOperation], + flags=[], + _rounding_decision=ALWAYS_ROUND, + Emax=999999999, + Emin=-999999999, + capitals=1 +) + +# Pre-made alternate contexts offered by the specification +# Don't change these; the user should be able to select these +# contexts and be able to reproduce results from other implementations +# of the spec. + +BasicContext = Context( + prec=9, rounding=ROUND_HALF_UP, + traps=[DivisionByZero, Overflow, InvalidOperation, Clamped, Underflow], + flags=[], +) + +ExtendedContext = Context( + prec=9, rounding=ROUND_HALF_EVEN, + traps=[], + flags=[], +) + + +##### Useful Constants (internal use only) #################### + +#Reusable defaults +Inf = Decimal('Inf') +negInf = Decimal('-Inf') + +#Infsign[sign] is infinity w/ that sign +Infsign = (Inf, negInf) + +NaN = Decimal('NaN') + + +##### crud for parsing strings ################################# +import re + +# There's an optional sign at the start, and an optional exponent +# at the end. The exponent has an optional sign and at least one +# digit. In between, must have either at least one digit followed +# by an optional fraction, or a decimal point followed by at least +# one digit. Yuck. + +_parser = re.compile(r""" +# \s* + (?P[-+])? + ( + (?P\d+) (\. (?P\d*))? + | + \. (?P\d+) + ) + ([eE](?P[-+]? \d+))? +# \s* + $ +""", re.VERBOSE).match #Uncomment the \s* to allow leading or trailing spaces. + +del re + +# return sign, n, p s.t. float string value == -1**sign * n * 10**p exactly + +def _string2exact(s): + m = _parser(s) + if m is None: + raise ValueError("invalid literal for Decimal: %r" % s) + + if m.group('sign') == "-": + sign = 1 + else: + sign = 0 + + exp = m.group('exp') + if exp is None: + exp = 0 + else: + exp = int(exp) + + intpart = m.group('int') + if intpart is None: + intpart = "" + fracpart = m.group('onlyfrac') + else: + fracpart = m.group('frac') + if fracpart is None: + fracpart = "" + + exp -= len(fracpart) + + mantissa = intpart + fracpart + tmp = map(int, mantissa) + backup = tmp + while tmp and tmp[0] == 0: + del tmp[0] + + # It's a zero + if not tmp: + if backup: + return (sign, tuple(backup), exp) + return (sign, (0,), exp) + mantissa = tuple(tmp) + + return (sign, mantissa, exp) + + +if __name__ == '__main__': + import doctest, sys + doctest.testmod(sys.modules[__name__]) diff --git a/docs/forms.txt b/docs/forms.txt index 329e84a1b1..f6cb55a3f6 100644 --- a/docs/forms.txt +++ b/docs/forms.txt @@ -567,6 +567,7 @@ check for the given property: * isValidANSIDate * isValidANSITime * isValidEmail + * isValidFloat * isValidImage * isValidImageURL * isValidPhone @@ -664,10 +665,10 @@ fails. If no message is passed in, a default message is used. Takes an integer argument and when called as a validator, checks that the field being validated is a power of the integer. -``IsValidFloat`` +``IsValidDecimal`` Takes a maximum number of digits and number of decimal places (in that - order) and validates whether the field is a float with less than the - maximum number of digits and decimal place. + order) and validates whether the field is a decimal with no more than the + maximum number of digits and decimal places. ``MatchesRegularExpression`` Takes a regular expression (a string) as a parameter and validates the diff --git a/docs/model-api.txt b/docs/model-api.txt index 1125d2810f..f42078eafb 100644 --- a/docs/model-api.txt +++ b/docs/model-api.txt @@ -184,6 +184,33 @@ A date and time field. Takes the same extra options as ``DateField``. The admin represents this as two ```` fields, with JavaScript shortcuts. +``DecimalField`` +~~~~~~~~~~~~~~ + +A fixed-precision decimal number, represented in Python by a ``Decimal`` instance. +Has two **required** arguments: + + ====================== =================================================== + Argument Description + ====================== =================================================== + ``max_digits`` The maximum number of digits allowed in the number. + + ``decimal_places`` The number of decimal places to store with the + number. + ====================== =================================================== + +For example, to store numbers up to 999 with a resolution of 2 decimal places, +you'd use:: + + models.DecimalField(..., max_digits=5, decimal_places=2) + +And to store numbers up to approximately one billion with a resolution of 10 +decimal places:: + + models.DecimalField(..., max_digits=19, decimal_places=10) + +The admin represents this as an ```` (a single-line input). + ``EmailField`` ~~~~~~~~~~~~~~ @@ -290,26 +317,7 @@ because the ``match`` applies to the base filename (``foo.gif`` and ``FloatField`` ~~~~~~~~~~~~~~ -A floating-point number. Has two **required** arguments: - - ====================== =================================================== - Argument Description - ====================== =================================================== - ``max_digits`` The maximum number of digits allowed in the number. - - ``decimal_places`` The number of decimal places to store with the - number. - ====================== =================================================== - -For example, to store numbers up to 999 with a resolution of 2 decimal places, -you'd use:: - - models.FloatField(..., max_digits=5, decimal_places=2) - -And to store numbers up to approximately one billion with a resolution of 10 -decimal places:: - - models.FloatField(..., max_digits=19, decimal_places=10) +A floating-point number represented in Python by a ``float`` instance. The admin represents this as an ```` (a single-line input). diff --git a/docs/newforms.txt b/docs/newforms.txt index 5516f60683..7ec4e9560c 100644 --- a/docs/newforms.txt +++ b/docs/newforms.txt @@ -1253,10 +1253,11 @@ the full list of conversions: ``CommaSeparatedIntegerField`` ``CharField`` ``DateField`` ``DateField`` ``DateTimeField`` ``DateTimeField`` + ``DecimalField`` ``DecimalField`` ``EmailField`` ``EmailField`` ``FileField`` ``CharField`` ``FilePathField`` ``CharField`` - ``FloatField`` ``CharField`` + ``FloatField`` ``FloatField`` ``ForeignKey`` ``ModelChoiceField`` (see below) ``ImageField`` ``CharField`` ``IntegerField`` ``IntegerField`` @@ -1281,6 +1282,11 @@ the full list of conversions: ``XMLField`` ``CharField`` with ``widget=Textarea`` =============================== ======================================== + +.. note:: + The ``FloatField`` form field and ``DecimalField`` model and form fields + are new in the development version. + As you might expect, the ``ForeignKey`` and ``ManyToManyField`` model field types are special cases: diff --git a/tests/modeltests/invalid_models/models.py b/tests/modeltests/invalid_models/models.py index af54ec3d35..90f2f54632 100644 --- a/tests/modeltests/invalid_models/models.py +++ b/tests/modeltests/invalid_models/models.py @@ -8,7 +8,7 @@ from django.db import models class FieldErrors(models.Model): charfield = models.CharField() - floatfield = models.FloatField() + decimalfield = models.DecimalField() filefield = models.FileField() prepopulate = models.CharField(maxlength=10, prepopulate_from='bad') choices = models.CharField(maxlength=10, choices='bad') @@ -87,10 +87,10 @@ class SelfClashM2M(models.Model): src_safe = models.CharField(maxlength=10) selfclashm2m = models.CharField(maxlength=10) - # Non-symmetrical M2M fields _do_ have related accessors, so + # Non-symmetrical M2M fields _do_ have related accessors, so # there is potential for clashes. selfclashm2m_set = models.ManyToManyField("SelfClashM2M", symmetrical=False) - + m2m_1 = models.ManyToManyField("SelfClashM2M", related_name='id', symmetrical=False) m2m_2 = models.ManyToManyField("SelfClashM2M", related_name='src_safe', symmetrical=False) @@ -108,8 +108,8 @@ class Car(models.Model): model = models.ForeignKey(Model) model_errors = """invalid_models.fielderrors: "charfield": CharFields require a "maxlength" attribute. -invalid_models.fielderrors: "floatfield": FloatFields require a "decimal_places" attribute. -invalid_models.fielderrors: "floatfield": FloatFields require a "max_digits" attribute. +invalid_models.fielderrors: "decimalfield": DecimalFields require a "decimal_places" attribute. +invalid_models.fielderrors: "decimalfield": DecimalFields require a "max_digits" attribute. invalid_models.fielderrors: "filefield": FileFields require an "upload_to" attribute. invalid_models.fielderrors: "prepopulate": prepopulate_from should be a list or tuple. invalid_models.fielderrors: "choices": "choices" should be iterable (e.g., a tuple or list). diff --git a/tests/regressiontests/forms/tests.py b/tests/regressiontests/forms/tests.py index 5939f7806c..ba5beed5e5 100644 --- a/tests/regressiontests/forms/tests.py +++ b/tests/regressiontests/forms/tests.py @@ -7,6 +7,10 @@ form_tests = r""" >>> import datetime >>> import time >>> import re +>>> try: +... from decimal import Decimal +... except ImportError: +... from django.utils._decimal import Decimal ########### # Widgets # @@ -1046,6 +1050,133 @@ Traceback (most recent call last): ... ValidationError: [u'Ensure this value is less than or equal to 20.'] +# FloatField ################################################################## + +>>> f = FloatField() +>>> f.clean('') +Traceback (most recent call last): +... +ValidationError: [u'This field is required.'] +>>> f.clean(None) +Traceback (most recent call last): +... +ValidationError: [u'This field is required.'] +>>> f.clean('1') +1.0 +>>> isinstance(f.clean('1'), float) +True +>>> f.clean('23') +23.0 +>>> f.clean('3.14') +3.1400000000000001 +>>> f.clean('a') +Traceback (most recent call last): +... +ValidationError: [u'Enter a number.'] +>>> f.clean('1.0 ') +1.0 +>>> f.clean(' 1.0') +1.0 +>>> f.clean(' 1.0 ') +1.0 +>>> f.clean('1.0a') +Traceback (most recent call last): +... +ValidationError: [u'Enter a number.'] + +>>> f = FloatField(required=False) +>>> f.clean('') + +>>> f.clean(None) + +>>> f.clean('1') +1.0 + +FloatField accepts min_value and max_value just like IntegerField: +>>> f = FloatField(max_value=1.5, min_value=0.5) + +>>> f.clean('1.6') +Traceback (most recent call last): +... +ValidationError: [u'Ensure this value is less than or equal to 1.5.'] +>>> f.clean('0.4') +Traceback (most recent call last): +... +ValidationError: [u'Ensure this value is greater than or equal to 0.5.'] +>>> f.clean('1.5') +1.5 +>>> f.clean('0.5') +0.5 + +# DecimalField ################################################################ + +>>> f = DecimalField(max_digits=4, decimal_places=2) +>>> f.clean('') +Traceback (most recent call last): +... +ValidationError: [u'This field is required.'] +>>> f.clean(None) +Traceback (most recent call last): +... +ValidationError: [u'This field is required.'] +>>> f.clean('1') +Decimal("1") +>>> isinstance(f.clean('1'), Decimal) +True +>>> f.clean('23') +Decimal("23") +>>> f.clean('3.14') +Decimal("3.14") +>>> f.clean('a') +Traceback (most recent call last): +... +ValidationError: [u'Enter a number.'] +>>> f.clean('1.0 ') +Decimal("1.0") +>>> f.clean(' 1.0') +Decimal("1.0") +>>> f.clean(' 1.0 ') +Decimal("1.0") +>>> f.clean('1.0a') +Traceback (most recent call last): +... +ValidationError: [u'Enter a number.'] +>>> f.clean('123.45') +Traceback (most recent call last): +... +ValidationError: [u'Ensure that there are no more than 4 digits in total.'] +>>> f.clean('1.234') +Traceback (most recent call last): +... +ValidationError: [u'Ensure that there are no more than 2 decimal places.'] +>>> f.clean('123.4') +Traceback (most recent call last): +... +ValidationError: [u'Ensure that there are no more than 2 digits before the decimal point.'] +>>> f = DecimalField(max_digits=4, decimal_places=2, required=False) +>>> f.clean('') + +>>> f.clean(None) + +>>> f.clean('1') +Decimal("1") + +DecimalField accepts min_value and max_value just like IntegerField: +>>> f = DecimalField(max_digits=4, decimal_places=2, max_value=Decimal('1.5'), min_value=Decimal('0.5')) + +>>> f.clean('1.6') +Traceback (most recent call last): +... +ValidationError: [u'Ensure this value is less than or equal to 1.5.'] +>>> f.clean('0.4') +Traceback (most recent call last): +... +ValidationError: [u'Ensure this value is greater than or equal to 0.5.'] +>>> f.clean('1.5') +Decimal("1.5") +>>> f.clean('0.5') +Decimal("0.5") + # DateField ################################################################### >>> import datetime diff --git a/tests/regressiontests/serializers_regress/models.py b/tests/regressiontests/serializers_regress/models.py index fea5c94cab..999b79ccaf 100644 --- a/tests/regressiontests/serializers_regress/models.py +++ b/tests/regressiontests/serializers_regress/models.py @@ -1,7 +1,7 @@ """ A test spanning all the capabilities of all the serializers. -This class sets up a model for each model field type +This class sets up a model for each model field type (except for image types, because of the PIL dependency). """ @@ -9,12 +9,12 @@ from django.db import models from django.contrib.contenttypes import generic from django.contrib.contenttypes.models import ContentType -# The following classes are for testing basic data +# The following classes are for testing basic data # marshalling, including NULL values. class BooleanData(models.Model): data = models.BooleanField(null=True) - + class CharData(models.Model): data = models.CharField(maxlength=30, null=True) @@ -24,6 +24,9 @@ class DateData(models.Model): class DateTimeData(models.Model): data = models.DateTimeField(null=True) +class DecimalData(models.Model): + data = models.DecimalField(null=True, decimal_places=3, max_digits=5) + class EmailData(models.Model): data = models.EmailField(null=True) @@ -34,7 +37,7 @@ class FilePathData(models.Model): data = models.FilePathField(null=True) class FloatData(models.Model): - data = models.FloatField(null=True, decimal_places=3, max_digits=5) + data = models.FloatField(null=True) class IntegerData(models.Model): data = models.IntegerField(null=True) @@ -145,6 +148,9 @@ class CharPKData(models.Model): # class DateTimePKData(models.Model): # data = models.DateTimeField(primary_key=True) +class DecimalPKData(models.Model): + data = models.DecimalField(primary_key=True, decimal_places=3, max_digits=5) + class EmailPKData(models.Model): data = models.EmailField(primary_key=True) @@ -155,7 +161,7 @@ class FilePathPKData(models.Model): data = models.FilePathField(primary_key=True) class FloatPKData(models.Model): - data = models.FloatField(primary_key=True, decimal_places=3, max_digits=5) + data = models.FloatField(primary_key=True) class IntegerPKData(models.Model): data = models.IntegerField(primary_key=True) diff --git a/tests/regressiontests/serializers_regress/tests.py b/tests/regressiontests/serializers_regress/tests.py index 317739dac4..5df4c6818a 100644 --- a/tests/regressiontests/serializers_regress/tests.py +++ b/tests/regressiontests/serializers_regress/tests.py @@ -2,7 +2,7 @@ A test spanning all the capabilities of all the serializers. This class defines sample data and a dynamically generated -test case that is capable of testing the capabilities of +test case that is capable of testing the capabilities of the serializers. This includes all valid data values, plus forward, backwards and self references. """ @@ -16,13 +16,17 @@ from django.db import transaction from django.core import management from models import * +try: + import decimal +except ImportError: + from django.utils import _decimal as decimal # A set of functions that can be used to recreate # test data objects of various kinds def data_create(pk, klass, data): instance = klass(id=pk) instance.data = data - instance.save() + instance.save() return instance def generic_create(pk, klass, data): @@ -32,13 +36,13 @@ def generic_create(pk, klass, data): for tag in data[1:]: instance.tags.create(data=tag) return instance - + def fk_create(pk, klass, data): instance = klass(id=pk) setattr(instance, 'data_id', data) instance.save() return instance - + def m2m_create(pk, klass, data): instance = klass(id=pk) instance.save() @@ -61,14 +65,14 @@ def pk_create(pk, klass, data): # test data objects of various kinds def data_compare(testcase, pk, klass, data): instance = klass.objects.get(id=pk) - testcase.assertEqual(data, instance.data, + testcase.assertEqual(data, instance.data, "Objects with PK=%d not equal; expected '%s' (%s), got '%s' (%s)" % (pk,data, type(data), instance.data, type(instance.data))) def generic_compare(testcase, pk, klass, data): instance = klass.objects.get(id=pk) testcase.assertEqual(data[0], instance.data) testcase.assertEqual(data[1:], [t.data for t in instance.tags.all()]) - + def fk_compare(testcase, pk, klass, data): instance = klass.objects.get(id=pk) testcase.assertEqual(data, instance.data_id) @@ -84,7 +88,7 @@ def o2o_compare(testcase, pk, klass, data): def pk_compare(testcase, pk, klass, data): instance = klass.objects.get(data=data) testcase.assertEqual(data, instance.data) - + # Define some data types. Each data type is # actually a pair of functions; one to create # and one to compare objects of that type @@ -96,7 +100,7 @@ o2o_obj = (o2o_create, o2o_compare) pk_obj = (pk_create, pk_compare) test_data = [ - # Format: (data type, PK value, Model Class, data) + # Format: (data type, PK value, Model Class, data) (data_obj, 1, BooleanData, True), (data_obj, 2, BooleanData, False), (data_obj, 10, CharData, "Test Char Data"), @@ -115,10 +119,14 @@ test_data = [ (data_obj, 51, FileData, None), (data_obj, 60, FilePathData, "/foo/bar/whiz.txt"), (data_obj, 61, FilePathData, None), - (data_obj, 70, FloatData, 12.345), - (data_obj, 71, FloatData, -12.345), - (data_obj, 72, FloatData, 0.0), - (data_obj, 73, FloatData, None), + (data_obj, 70, DecimalData, decimal.Decimal('12.345')), + (data_obj, 71, DecimalData, decimal.Decimal('-12.345')), + (data_obj, 72, DecimalData, decimal.Decimal('0.0')), + (data_obj, 73, DecimalData, None), + (data_obj, 74, FloatData, 12.345), + (data_obj, 75, FloatData, -12.345), + (data_obj, 76, FloatData, 0.0), + (data_obj, 77, FloatData, None), (data_obj, 80, IntegerData, 123456789), (data_obj, 81, IntegerData, -123456789), (data_obj, 82, IntegerData, 0), @@ -137,10 +145,10 @@ test_data = [ (data_obj, 131, PositiveSmallIntegerData, None), (data_obj, 140, SlugData, "this-is-a-slug"), (data_obj, 141, SlugData, None), - (data_obj, 150, SmallData, 12), - (data_obj, 151, SmallData, -12), - (data_obj, 152, SmallData, 0), - (data_obj, 153, SmallData, None), + (data_obj, 150, SmallData, 12), + (data_obj, 151, SmallData, -12), + (data_obj, 152, SmallData, 0), + (data_obj, 153, SmallData, None), (data_obj, 160, TextData, """This is a long piece of text. It contains line breaks. Several of them. @@ -188,7 +196,7 @@ The end."""), (fk_obj, 450, FKDataToField, "UAnchor 1"), (fk_obj, 451, FKDataToField, "UAnchor 2"), (fk_obj, 452, FKDataToField, None), - + (data_obj, 500, Anchor, "Anchor 3"), (data_obj, 501, Anchor, "Anchor 4"), (data_obj, 502, UniqueAnchor, "UAnchor 2"), @@ -201,9 +209,12 @@ The end."""), (pk_obj, 640, EmailPKData, "hovercraft@example.com"), (pk_obj, 650, FilePKData, 'file:///foo/bar/whiz.txt'), (pk_obj, 660, FilePathPKData, "/foo/bar/whiz.txt"), - (pk_obj, 670, FloatPKData, 12.345), - (pk_obj, 671, FloatPKData, -12.345), - (pk_obj, 672, FloatPKData, 0.0), + (pk_obj, 670, DecimalPKData, decimal.Decimal('12.345')), + (pk_obj, 671, DecimalPKData, decimal.Decimal('-12.345')), + (pk_obj, 672, DecimalPKData, decimal.Decimal('0.0')), + (pk_obj, 673, FloatPKData, 12.345), + (pk_obj, 674, FloatPKData, -12.345), + (pk_obj, 675, FloatPKData, 0.0), (pk_obj, 680, IntegerPKData, 123456789), (pk_obj, 681, IntegerPKData, -123456789), (pk_obj, 682, IntegerPKData, 0), @@ -215,9 +226,9 @@ The end."""), (pk_obj, 720, PositiveIntegerPKData, 123456789), (pk_obj, 730, PositiveSmallIntegerPKData, 12), (pk_obj, 740, SlugPKData, "this-is-a-slug"), - (pk_obj, 750, SmallPKData, 12), - (pk_obj, 751, SmallPKData, -12), - (pk_obj, 752, SmallPKData, 0), + (pk_obj, 750, SmallPKData, 12), + (pk_obj, 751, SmallPKData, -12), + (pk_obj, 752, SmallPKData, 0), # (pk_obj, 760, TextPKData, """This is a long piece of text. # It contains line breaks. # Several of them. @@ -226,7 +237,7 @@ The end."""), (pk_obj, 780, USStatePKData, "MA"), # (pk_obj, 790, XMLPKData, ""), ] - + # Dynamically create serializer tests to ensure that all # registered serializers are automatically tested. class SerializerTests(unittest.TestCase): @@ -234,7 +245,7 @@ class SerializerTests(unittest.TestCase): def serializerTest(format, self): # Clear the database first - management.flush(verbosity=0, interactive=False) + management.flush(verbosity=0, interactive=False) # Create all the objects defined in the test data objects = [] @@ -245,14 +256,14 @@ def serializerTest(format, self): transaction.commit() transaction.leave_transaction_management() - # Add the generic tagged objects to the object list + # Add the generic tagged objects to the object list objects.extend(Tag.objects.all()) - + # Serialize the test database serialized_data = serializers.serialize(format, objects, indent=2) # Flush the database and recreate from the serialized data - management.flush(verbosity=0, interactive=False) + management.flush(verbosity=0, interactive=False) transaction.enter_transaction_management() transaction.managed(True) for obj in serializers.deserialize(format, serialized_data): @@ -260,10 +271,10 @@ def serializerTest(format, self): transaction.commit() transaction.leave_transaction_management() - # Assert that the deserialized data is the same + # Assert that the deserialized data is the same # as the original source for (func, pk, klass, datum) in test_data: func[1](self, pk, klass, datum) - + for format in serializers.get_serializer_formats(): setattr(SerializerTests, 'test_'+format+'_serializer', curry(serializerTest, format))