Re: [pygame] converting byte image for display

[Guillaume Proux <gproux@xxxxxxxxx>]

Very nice...

It seems some old tricks do not apply anymore.
In any case, getting rid of function calls in inner loops are always a
good idea even with the newest list comprehension optimizations.

Regards,

Guillaume

Guillaume

On 1/2/06, Trevor Fancher <trevor@xxxxxxxxxxx> wrote:
>
> On Jan 1, 2006, at 9:00 PM, Simon Wittber wrote:
> > Benchmarks are fun.
>
> Sure are.  :)
>
>
> > In your test_concat function, you are testing a function call as well
> > as the concat process. This will add extra time to that benchmark,
> > which the other benchmarks don't have.
>
> I noticed this but left the function call in on purpose because that
> is what the original poster was going to be doing anyways.
>
>
> > Also, you are using a very small 3 item list for the test. a 320x200
> > 256 color image will have 64000 bytes.
> >
> > Using
> >
> > test_list = "a" * 64000
> > test_count = 100
> >
> > these were my results:
> >
> > concat: 6.103
> >   map1: 6.349
> >   map2: 6.303
> >
> > String concantenation used to be quite slow in Python 2.3, but has
> > since recieved some optimisation.
> >
> > http://mail.python.org/pipermail/python-list/2004-September/
> > 242125.html
>
> http://mail.python.org doesn't want to load for me but
> http://python.org will, weird.
>
> Anyways, it appears that string concatenation is now faster than using
> the built-in function join and map.
>
>
> > Also, you may want to try using a list comprehension, which will be
> > quite fast.
> >
> > def test_list_comp(test_count, test_list):
> >    t = pygame.time.get_ticks()
> >    for i in range(test_count):
> >       a = ''.join([i*3 for i in test_list])
> >    return pygame.time.get_ticks() - t
> >
> >
> > This score 2.743 on my box.
>
> Yep, list comprehension was significantly faster on my box too.  Thanks
> for the suggestion.
>
>
> > -Sw.
> __
> Trevor Fancher
> http://fancher.org
>
>
>
>