Tim Roberts <[EMAIL PROTECTED]> wrote: ... > xrange used to be better. As I understand it, that's no longer the case.
measuring is better than guessing: brain:~/codejam alex$ python -V Python 2.5c1 brain:~/codejam alex$ python -mtimeit 'for x in range(1000):pass' 10000 loops, best of 3: 71.9 usec per loop brain:~/codejam alex$ python -mtimeit 'for x in xrange(1000):pass' 10000 loops, best of 3: 54 usec per loop brain:~/codejam alex$ python -mtimeit -s'y=range(1000)' 'for x in y:pass' 10000 loops, best of 3: 44.8 usec per loop brain:~/codejam alex$ python -mtimeit -s'y=xrange(1000)' 'for x in y:pass' 10000 loops, best of 3: 53.2 usec per loop brain:~/codejam alex$ So: in 2.5 (2.4 too, do your own timings;-) range is better if you can create the range once and use it repeatedly, xrange if you have to create the range each time. But actually: brain:~/codejam alex$ python -mtimeit -s'from itertools import repeat' 'for x in repeat(None, 1000): pass' 10000 loops, best of 3: 41.3 usec per loop if you don't actually need the iteration-index in the loop (you just need to repeat the loop N times), itertools.repeat is even better (well, if every microsecond counts, anyway;-). Alex -- http://mail.python.org/mailman/listinfo/python-list
