[issue15438] Incredible issue in math.pow
andrea bergamini added the comment: Ok guys, ticket closed, but I'm still confused: I'm not a Python expert, I've understood that math is a sort of wrapper of C math.h or something like this, but: - I can't find any reason in using math.pow if I can get errors like the one explained. - I've used math.h in my C++ code without having experienced any problem in that pow operation. I'm surely missing something but I'm a bit confused... -- status: open -> closed ___ Python tracker <http://bugs.python.org/issue15438> ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue15438] Incredible issue in math.pow
andrea bergamini added the comment: Well, from a library I'm used to expect a good result or an exception. Not a value that differs from the correct of one unit! I agree with Antoine, the doc should warn about this behavior. I've lost a lot of time before discovering my application issue came from the py math library... -- ___ Python tracker <http://bugs.python.org/issue15438> ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue15438] Incredible issue in math.pow
andrea bergamini added the comment: Ok, but math.pow IMPO has to be aligned to pow and built-in pow (**), otherwise this kind of "inaccuracies" can compromise the application behavior. I was using this funcion in a cryptographic mechanisms, and this issue resulted in a failure. Generally speaking, integer numbers should not be affected by inaccuracies. I mean, there's no floating point. -- ___ Python tracker <http://bugs.python.org/issue15438> ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue15438] Incredible issue in math.pow
New submission from andrea bergamini : math.pow(43, 10) gives the wrong result: 21611482313284248.0 Instead, the build-in function 43**10 and pow(43, 10) give the correct result: 21611482313284249L. This bug has been seen on ActivePython 2.5.1.1. Sorry no tests on recent versions. -- components: Library (Lib) messages: 166275 nosy: andrea.bergamini priority: normal severity: normal status: open title: Incredible issue in math.pow type: behavior ___ Python tracker <http://bugs.python.org/issue15438> ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
