Message 91886 - Python tracker
$ python3.1 Python 3.1 (r31:73572, Jul 6 2009, 21:21:12) [GCC 4.4.0 20090506 (Red Hat 4.4.0-4)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import math >>> math.log10(1000) 3.0 >>> math.log(1000, 10) 2.9999999999999996 You would expect the results to be the same. Internally math.log() could call math.log10() when base==10. That would ensure they are consistent.