Mark Dickinson added the comment:
Sorry: that was nonsense. trunc is fine---it's round, floor and ceil that
fail on large arguments with this patch:
>>> import decimal, math
>>> math.floor(decimal.Decimal("1e30"))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/dickinsm/python_source/py3k/Lib/decimal.py", line 1475, in
__floor__
return trunc(self.quantize(Decimal(1), rounding=ROUND_FLOOR))
File "/Users/dickinsm/python_source/py3k/Lib/decimal.py", line 2265, in
quantize
'quantize result has too many digits for current context')
File "/Users/dickinsm/python_source/py3k/Lib/decimal.py", line 3546, in
_raise_error
raise error(explanation)
decimal.InvalidOperation: quantize result has too many digits for current
context
>>> round(decimal.Decimal("1e30"))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/dickinsm/python_source/py3k/Lib/decimal.py", line 1487, in
__round__
return trunc(self.quantize(Decimal(1), rounding=ROUND_HALF_EVEN))
File "/Users/dickinsm/python_source/py3k/Lib/decimal.py", line 2265, in
quantize
'quantize result has too many digits for current context')
File "/Users/dickinsm/python_source/py3k/Lib/decimal.py", line 3546, in
_raise_error
raise error(explanation)
decimal.InvalidOperation: quantize result has too many digits for current
context
>>>
Can I suggest using _rescale instead of quantize? For example,
def __round__(self, ndigits:_numbers.Integral=None):
"""Rounds self to ndigits decimal places, defaulting to 0.
If ndigits is omitted or None, returns an int, otherwise a
Decimal. Rounds half toward even."""
if ndigits is None:
return trunc(self._rescale(0, rounding=ROUND_HALF_EVEN))
return self._rescale(-ndigits, rounding=ROUND_HALF_EVEN)
__________________________________
Tracker <[EMAIL PROTECTED]>
<http://bugs.python.org/issue1623>
__________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe:
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
