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Re: Speeding up permutations generation

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  Re: Speeding up permutations generation Gene Heskett <gheskett@wdtv.com> - 2015-03-06 05:32 -0500

#87012 — Re: Speeding up permutations generation

On Friday 06 March 2015 03:24:48 Abhiram R wrote:
> > A list of 100 elements has approximately 9.33 x 10**157
> > permutations. If you could somehow generate one permutation every
> > yoctosecond, exhausting them would still take more than a hundred
> > orders of magnitude longer than the age of the universe.
> > --
> > https://mail.python.org/mailman/listinfo/python-list
>
> ​True that :D I may have exaggerated on the number. Let's consider
> something more practically manageable​ => 50 elements with a 50!
> permutation.
> Is there a solution now?

Yes, but its now only 8.881784197e+84 elements so it is still not a 
practical target.  Doing all elements of a matrix is generally equ to 
n!, and 50 raised to the 50th power is still a number that will probably 
use up this suns remaining lifetime doing it in assembly.  If submitted 
and accepted to BOINC with its parallelism potential.  And 
Seagate/Western Digital's combined output for about that same time to 
store the result.

I'd choose any other, perhaps less exhaustive method.  Or a more 
practical size of dataset parameters.

> ​-Abhiram.R
> *~Never give up*

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>

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