On Wednesday, July 6, 2011, Maximilian Trescher <fau...@trescher-it.de> wrote: > Hi, > > i just committed a fix for issue #135, which is about timedelta rounding. > > The problem was in drange: > before the fix it used numpy.arange which resulted in rounding issues, > the numpy doc says about arange: > "When using a non-integer step, such as 0.1, the results will often not > be consistent. It is better to use linspace for these cases." > > So i tried to create a fix involving linspace, > you can see it here: > https://github.com/faucon/matplotlib/commit/06195c35f4348f37002e850d1cee992d07f5a29c > > it works (and is the only way i found to avoid the roundig issues) but > it feels somehow "hackish". > > An alternative would be the following implementation, which is quite > readable but much slower: > > def drange(dstart, dend, delta): # its very slow > """ > Return a date range as float Gregorian ordinals. *dstart* and > *dend* are :class:`datetime` instances. *delta* is a > :class:`datetime.timedelta` instance. > """ > dloop = dstart > datelist = [] > while dloop < dend: > datelist.append(dloop) > dloop += delta > return dates.date2num(datelist) > > > i will try to add a test the next days. Then i would create a > pull-request if the fix looks reasonable to you. > > thanks, > > Maximilian > >
Thanks for patching. I haven't tested it yet, but the linspace solution is probably the best way to go. I would avoid drange because I believe numpy will soon be implementing such a function and I wouldn't want the possible confusion that comes from that. Ben Root ------------------------------------------------------------------------------ All of the data generated in your IT infrastructure is seriously valuable. Why? It contains a definitive record of application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-d2d-c2 _______________________________________________ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
