Em Seg, 2006-04-03 às 08:47 -0700, JuHui escreveu:
> which one has best performance?
Let's see...
> a:for i in range(0,len(a))
$ python2.4 -mtimeit -s 'a=[None]*100' 'for i in range(len(a)):
j = a[i]
'
100000 loops, best of 3: 17.7 usec per loop
$ python2.4 -mtimeit -s 'a=[None]*100' 'for i in xrange(len(a)):
j = a[i]
'
100000 loops, best of 3: 16.8 usec per loop
> b:for x in a
$ python2.4 -mtimeit -s 'a=[None]*100' 'i = 0
for j in a:
i += 1
'
100000 loops, best of 3: 15.7 usec per loop
> c:for x,y in enumerate(a)
$ python2.4 -mtimeit -s 'a=[None]*100' 'for i, j in enumerate(a):
pass
'
100000 loops, best of 3: 12.9 usec per loop
Using enumerate is cleaner and faster.
HTH,
--
Felipe.
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