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authorSteve Dower <steve.dower@microsoft.com>2017-02-06 14:12:19 -0800
committerSteve Dower <steve.dower@microsoft.com>2017-02-06 14:12:19 -0800
commit5b4df5813c20fe96f117d0201965b52e86a1a66d (patch)
treed991f61bc824ca1b1b92bf7fb16fe3dacd4b1335 /Lib/_pydecimal.py
parent3e0bdff8a0793d305b972f4a653e4698d440b3ae (diff)
parent95b272b4e0d5438a12702e51e05d03f5a5a8e505 (diff)
downloadcpython-5b4df5813c20fe96f117d0201965b52e86a1a66d.tar.gz
Includes ensurepip and venv packages in nuget package.
Diffstat (limited to 'Lib/_pydecimal.py')
-rw-r--r--Lib/_pydecimal.py62
1 files changed, 56 insertions, 6 deletions
diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index a5ea340e9d..0b40928ff8 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -148,7 +148,7 @@ __xname__ = __name__ # sys.modules lookup (--without-threads)
__name__ = 'decimal' # For pickling
__version__ = '1.70' # Highest version of the spec this complies with
# See http://speleotrove.com/decimal/
-__libmpdec_version__ = "2.4.1" # compatible libmpdec version
+__libmpdec_version__ = "2.4.2" # compatible libmpdec version
import math as _math
import numbers as _numbers
@@ -589,7 +589,7 @@ class Decimal(object):
# From a string
# REs insist on real strings, so we can too.
if isinstance(value, str):
- m = _parser(value.strip())
+ m = _parser(value.strip().replace("_", ""))
if m is None:
if context is None:
context = getcontext()
@@ -1010,6 +1010,56 @@ class Decimal(object):
"""
return DecimalTuple(self._sign, tuple(map(int, self._int)), self._exp)
+ def as_integer_ratio(self):
+ """Express a finite Decimal instance in the form n / d.
+
+ Returns a pair (n, d) of integers. When called on an infinity
+ or NaN, raises OverflowError or ValueError respectively.
+
+ >>> Decimal('3.14').as_integer_ratio()
+ (157, 50)
+ >>> Decimal('-123e5').as_integer_ratio()
+ (-12300000, 1)
+ >>> Decimal('0.00').as_integer_ratio()
+ (0, 1)
+
+ """
+ if self._is_special:
+ if self.is_nan():
+ raise ValueError("cannot convert NaN to integer ratio")
+ else:
+ raise OverflowError("cannot convert Infinity to integer ratio")
+
+ if not self:
+ return 0, 1
+
+ # Find n, d in lowest terms such that abs(self) == n / d;
+ # we'll deal with the sign later.
+ n = int(self._int)
+ if self._exp >= 0:
+ # self is an integer.
+ n, d = n * 10**self._exp, 1
+ else:
+ # Find d2, d5 such that abs(self) = n / (2**d2 * 5**d5).
+ d5 = -self._exp
+ while d5 > 0 and n % 5 == 0:
+ n //= 5
+ d5 -= 1
+
+ # (n & -n).bit_length() - 1 counts trailing zeros in binary
+ # representation of n (provided n is nonzero).
+ d2 = -self._exp
+ shift2 = min((n & -n).bit_length() - 1, d2)
+ if shift2:
+ n >>= shift2
+ d2 -= shift2
+
+ d = 5**d5 << d2
+
+ if self._sign:
+ n = -n
+ return n, d
+
def __repr__(self):
"""Represents the number as an instance of Decimal."""
# Invariant: eval(repr(d)) == d
@@ -4075,7 +4125,7 @@ class Context(object):
This will make it round up for that operation.
"""
rounding = self.rounding
- self.rounding= type
+ self.rounding = type
return rounding
def create_decimal(self, num='0'):
@@ -4084,10 +4134,10 @@ class Context(object):
This method implements the to-number operation of the
IBM Decimal specification."""
- if isinstance(num, str) and num != num.strip():
+ if isinstance(num, str) and (num != num.strip() or '_' in num):
return self._raise_error(ConversionSyntax,
- "no trailing or leading whitespace is "
- "permitted.")
+ "trailing or leading whitespace and "
+ "underscores are not permitted.")
d = Decimal(num, context=self)
if d._isnan() and len(d._int) > self.prec - self.clamp: