Speed up this code?

Frank Millman frank at chagford.com
Sat May 27 09:23:40 CEST 2006


Gregory Petrosyan wrote:
> # Paul Rubin's version
> gregory at home:~$ python -mtimeit "import test2" "test2.primes(1000)"
> 100 loops, best of 3: 14.3 msec per loop
>
> # version from the Cookbook
> gregory at home:~$ python -mtimeit "import test1" "test1.primes(1000)"
> 1000 loops, best of 3: 528 usec per loop

You are quite right, Gregory, my timings are way off.

I have figured out my mistake. Paul's function is a generator. Unlike a
normal function, when you call a generator function, it does not
actually run the entire function, it simply returns a generator object.
It only runs when you iterate over it until it is exhausted. I was
effectively measuring how long it took to *create* the generator, not
iterate over it.

Thanks for correcting me.

Frank




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