New submission from felix.engelmann <fe-python-b...@nlogn.org>: As described in https://www.python.org/dev/peps/pep-0327/#rounding-algorithms round-half-up: If the discarded digits represent greater than or equal to half (0.5) then the result should be incremented by 1; otherwise the discarded digits are ignored.
Rounding 9.95 to 1 decimal with ROUND_HALD_UP results in 9.9 instead of 10.0: Decimal(9.95).quantize(Decimal('1.1'),ROUND_HALF_UP) Out[49]: Decimal('9.9') It does not matter at wich position this rounding with influence on another digit happens: Decimal(9.995).quantize(Decimal('1.11'),ROUND_HALF_UP) Out[50]: Decimal('9.99') It is a specific problem with the 5, because 9.96 works as expected Decimal(9.96).quantize(Decimal('1.1'),ROUND_HALF_UP) Out[40]: Decimal('10.0') System: Python 3.6.4 import decimal decimal.__version__ : '1.70' ---------- components: Library (Lib) messages: 312546 nosy: felix.engelmann priority: normal severity: normal status: open title: decimal ROUND_HALF_UP not according to spec for 9.95 to 10.0 type: behavior versions: Python 3.6 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue32908> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com