Might using min(ceil((stop-start)/step), ceil((stop-start)/step-r))
with r = finfo(double).resolution instead of ceil((stop-start)/step) perhaps be useful? Joris On 14 Sep 2007, at 11:37, Ed Schofield wrote: > Hi everyone, > > This was reported yesterday as a bug in Debian's numpy package: > >>>> len(numpy.arange(0, 0.6, 0.1)) == len(numpy.arange(0, 0.4+0.2, >>>> 0.1)) > False > > The cause is this: > >>>> ceil((0.4+0.2)/0.1) > 7.0 > >>>> ceil(0.6/0.1) > 6.0 > > which holds for both numpy's and the standard library's ceil(). > > Using arange in this way is a fundamentally unreliable thing to do, > but is there anything we want to do about this? Should numpy emit a > warning when using arange with floating point values when > (stop-start)/step is close to an integer? > > -- Ed Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
