Issue 11131: Fix sign of zero result on plus and minus operations in ROUND_FLOOR rounding mode.

This commit is contained in:
Mark Dickinson 2011-03-12 11:05:32 +00:00
parent d4f016fb51
commit 2c8c62e64d
3 changed files with 84 additions and 8 deletions

View File

@ -1068,14 +1068,16 @@ class Decimal(object):
if ans:
return ans
if not self:
# -Decimal('0') is Decimal('0'), not Decimal('-0')
if context is None:
context = getcontext()
if not self and context.rounding != ROUND_FLOOR:
# -Decimal('0') is Decimal('0'), not Decimal('-0'), except
# in ROUND_FLOOR rounding mode.
ans = self.copy_abs()
else:
ans = self.copy_negate()
if context is None:
context = getcontext()
return ans._fix(context)
def __pos__(self, context=None):
@ -1088,14 +1090,15 @@ class Decimal(object):
if ans:
return ans
if not self:
# + (-0) = 0
if context is None:
context = getcontext()
if not self and context.rounding != ROUND_FLOOR:
# + (-0) = 0, except in ROUND_FLOOR rounding mode.
ans = self.copy_abs()
else:
ans = Decimal(self)
if context is None:
context = getcontext()
return ans._fix(context)
def __abs__(self, round=True, context=None):

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@ -2745,3 +2745,73 @@ pwmx437 power 17 1728 1729 -> 1
pwmx438 power 18 1728 1729 -> 1
pwmx439 power 19 1728 1729 -> 456
pwmx440 power 20 1728 1729 -> 1
-- plus and minus zero in various rounding modes (see issue 11131)
extended: 1
precision: 9
maxexponent: 384
minexponent: -383
rounding: half_even
plux1000 plus 0.0 -> 0.0
plux1001 plus -0.0 -> 0.0
minx1000 minus 0.0 -> 0.0
minx1001 minus -0.0 -> 0.0
absx1000 abs 0.0 -> 0.0
absx1001 abs -0.0 -> 0.0
rounding: half_up
plux1010 plus 0.0 -> 0.0
minx1010 minus 0.0 -> 0.0
plux1011 plus -0.0 -> 0.0
minx1011 minus -0.0 -> 0.0
absx1010 abs 0.0 -> 0.0
absx1011 abs -0.0 -> 0.0
rounding: ceiling
plux1020 plus 0.0 -> 0.0
minx1020 minus 0.0 -> 0.0
plux1021 plus -0.0 -> 0.0
minx1021 minus -0.0 -> 0.0
absx1020 abs 0.0 -> 0.0
absx1021 abs -0.0 -> 0.0
rounding: floor
plux1030 plus 0.0 -> 0.0
minx1030 minus 0.0 -> -0.0
plux1031 plus -0.0 -> -0.0
minx1031 minus -0.0 -> 0.0
absx1030 abs 0.0 -> 0.0
absx1031 abs -0.0 -> 0.0
rounding: down
plux1040 plus 0.0 -> 0.0
minx1040 minus 0.0 -> 0.0
plux1041 plus -0.0 -> 0.0
minx1041 minus -0.0 -> 0.0
absx1040 abs 0.0 -> 0.0
absx1041 abs -0.0 -> 0.0
rounding: up
plux1050 plus 0.0 -> 0.0
minx1050 minus 0.0 -> 0.0
plux1051 plus -0.0 -> 0.0
minx1051 minus -0.0 -> 0.0
absx1050 abs 0.0 -> 0.0
absx1051 abs -0.0 -> 0.0
rounding: half_down
plux1060 plus 0.0 -> 0.0
minx1060 minus 0.0 -> 0.0
plux1061 plus -0.0 -> 0.0
minx1061 minus -0.0 -> 0.0
absx1060 abs 0.0 -> 0.0
absx1061 abs -0.0 -> 0.0
rounding: 05up
plux1070 plus 0.0 -> 0.0
minx1070 minus 0.0 -> 0.0
plux1071 plus -0.0 -> 0.0
minx1071 minus -0.0 -> 0.0
absx1070 abs 0.0 -> 0.0
absx1071 abs -0.0 -> 0.0

View File

@ -43,6 +43,9 @@ Core and Builtins
Library
-------
- Issue #11131: Fix sign of zero in plus and minus operations when
the context rounding mode is ROUND_FLOOR.
- Issue #5622: Fix curses.wrapper to raise correct exception if curses
initialization fails.