On 11/10/2012 10:55, Damon McDougall wrote: > On Wed, Oct 10, 2012 at 5:00 PM, Benjamin Root <ben.r...@ou.edu> wrote: >> >> >> On Wed, Oct 10, 2012 at 10:55 AM, Mark Lawrence <breamore...@yahoo.co.uk> >> wrote: >>> >>> On 10/10/2012 15:41, Mark Lawrence wrote: >>>> On 10/10/2012 14:29, Benjamin Root wrote: >>>>> >>>>> I know of a few people who have difficulties with matplotlib's datetime >>>>> handling, but they are usually operating on the scale of milliseconds >>>>> or >>>>> less (lightning data), in which case, one is already at the edge of the >>>>> resolution handled by python's datetime objects. However, we would >>>>> certainly welcome any sort of examples of how matplotlib fails in >>>>> handling >>>>> seconds scale and lower plots. >>>>> >>>>> Cheers! >>>>> Ben Root >>>>> >>>>> >>>> >>>> I'll assume that the milliseconds above is a typo. From >>>> http://docs.python.org/library/datetime.html "class datetime.timedelta A >>>> duration expressing the difference between two date, time, or datetime >>>> instances to microsecond resolution." Still, what's a factor of 1000 >>>> amongst friends? :) >>>> >>> >>> http://www.python.org/dev/peps/pep-0418/ has been implemented in Python >>> 3.3 and talks about clocks with nanosecond resolutions. I've flagged it >>> up here just in case people weren't aware. >>> >> >> Ah, you are right, I meant microseconds. >> >> With apologies to Spaceballs: >> >> "Prepare to go to microsecond resolution!" >> "No, no, microsecond resolution is too slow" >> "Microsecond resolution is too slow?" >> "Yes, too slow. We must use nanosecond resolution!" >> "Prep-- Prepare Python, for nanosecond resolution!" >> >> Cheers! >> Ben Root > > Am I missing something here? Are seconds just floats internally? A > delta of 1e-6 is nothing (pardon the pun). A delta of 1e-9 is the > *least* I'd expect. Maybe even 1e-12. Perhaps the python interpreter > doesn't do any > denormalising<http://stackoverflow.com/questions/9314534/why-does-changing-0-1f-to-0-slow-down-performance-by-10x> > when encountered with deltas very close to zero... >
What percentage of computer users wants a delta of 1e-12? I suspect that the vast majority of users couldn't care two hoots about miniscule time deltas in a world where changing time zones can cause chaos. Where some applications cannot handle years before 1970, or 1904, or 1900 or whatever. Or they can't go too far forward, 2036 I think but don't quote me. Where people like myself had to put a huge amount of effort into changing code so that applications would carry on working when the date flipped over from 31st December 1999 to 1st January 2000. If things were that simple why is matplotlib using third party modules like dateutil and pytz? Why doesn't the "batteries included" Python already provide this functionality? -- Cheers. Mark Lawrence. ------------------------------------------------------------------------------ Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
