I could use some help making this Python code run faster using only Python code.

[Python Maniac]

On Sep 21, 12:56 am, Duncan Booth <duncan.bo... at invalid.invalid>
wrote:
> George Sakkis <george.sak... at gmail.com> wrote:
> > It has to do with the input string length; try multiplying it by 10 or
> > 100. Below is a more complete benchmark; for largish strings, the imap
> > version is the fastest among those using the original algorithm. Of
> > course using a lookup table as Diez showed is even faster. FWIW, here
> > are some timings (Python 2.5, WinXP):
>
> > scramble:       1.818
> > scramble_listcomp:      1.492
> > scramble_gencomp:       1.535
> > scramble_map:   1.377
> > scramble_imap:  1.332
> > scramble_dict:  0.817
> > scramble_dict_map:      0.419
> > scramble_dict_imap:     0.410
>
> I added another one:
>
> import string
> scramble_translation = string.maketrans(''.join(chr(i) for i in xrange
> (256)), ''.join(chr(i|0x80) for i in xrange(256)))
> def scramble_translate(line):
>     return string.translate(line, scramble_translation)
>
> ...
>     funcs = [scramble, scramble_listcomp, scramble_gencomp,
>              scramble_map, scramble_imap,
>              scramble_dict, scramble_dict_map, scramble_dict_imap,
>              scramble_translate
>          ]
>
> and I think I win:
>
> scramble:       1.949
> scramble_listcomp:      1.439
> scramble_gencomp:       1.455
> scramble_map:   1.470
> scramble_imap:  1.546
> scramble_dict:  0.914
> scramble_dict_map:      0.415
> scramble_dict_imap:     0.416
> scramble_translate:     0.007

Some benchmarks showing the effectiveness of using Psyco:

scramble:       4.210
scramble_listcomp:      2.343
scramble_gencomp:       2.599
scramble_map:   1.960
scramble_imap:  2.231
scramble_dict:  2.387
scramble_dict_map:      0.535
scramble_dict_imap:     0.726
scramble_translate:     0.010

Now with Psyco...
psyco.bind(scramble)...
scramble:       0.121   4.088   34.670x faster
scramble_listcomp:      0.215   2.128   10.919x faster
scramble_gencomp:       2.563   0.036   1.014x faster
scramble_map:   2.002   -0.043  0.979x slower
scramble_imap:  2.175   0.056   1.026x faster
scramble_dict:  0.199   2.188   11.983x faster
scramble_dict_map:      0.505   0.029   1.058x faster
scramble_dict_imap:     0.728   -0.001  0.998x slower
scramble_translate:     0.009   0.001   1.111x faster

Overall, Psyco helped my little process of converting 20 MB worth of
ASCII into what may not look like the original at 6x faster than
without Psyco.