On 9 August 2014 06:08, Steven D'Aprano <st...@pearwood.info> wrote: > py> with Stopwatch(): > ... sum(carray) # carray is a numpy array of 75000000 floats. > ... > 112500000.0 > time taken: 52.659770 seconds > py> with Stopwatch(): > ... numpy.sum(carray) > ... > 112500000.0 > time taken: 0.161263 seconds > > >> Why have builtin sum at all if its use comes with so many caveats? > > Because sum() is a perfectly reasonable general purpose tool for adding > up small amounts of numbers where high floating point precision is not > required. It has been included as a built-in because Python comes with > "batteries included", and a basic function for adding up a few numbers > is an obvious, simple battery. But serious programmers should be > comfortable with the idea that you use the right tool for the right job.
Changing the subject a little, but the Stopwatch function you used up there is "an obvious, simple battery" for timing a chunk of code at the interactive prompt. I'm amazed there's nothing like it in the timeit module... Paul _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
