Re: efficiency of range() and xrange() in for loops


Steve R. Hastings wrote:
When you compile the expression

for i in range(1000):
pass

does Python make an iterator for range(), and then generate the values
on the fly? Or does Python actually allocate the list [0, 1, 2, ..., 999]
and then step through it?

I ran an experiment on this a while back. I thought it generated a
list. But the results turned out to be surprising. Take this with a
grain of salt. I'm not completely sure I did what I meant to do. But
it looks like however you do it, it works out about the same.

http://www.signalsguru.net/articles/pyloops/pyloops.html

.

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