Re^4: Algorithm RFC: fast (pseudo-)random shuffle with no repetition

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Re^5: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by karlgoethebier (Abbot) on Sep 24, 2023 at 14:09 UTC
Do you mean like this `(1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8)`? Because then I actually get more results quickly. However, something is not quite right with the regular expressions. I must be swapping `$m3` with `$m2`. This is a bit of a mystery to me at the moment. «The Crux of the Biscuit is the Apostrophe»	[reply] [d/l] [select]
Re^6: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by LanX (Saint) on Sep 24, 2023 at 14:31 UTC
I didn't run your code, and I don't trust it either. But I assumed you wanted a brute force try and error shuffling. > Do you mean like this `(1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8)` Yes. And there is only one possible solution `(1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 1, 8, 1)` Trying 1e15 shuffles to finally get there seems like a good way to transform your hardware into an electric heater only. Cheers Rolf _{(addicted to the Perl Programming Language :) see Wikisyntax for the Monastery}	[reply] [d/l] [select]
Re^7: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by hv (Prior) on Sep 24, 2023 at 16:27 UTC
there is only one possible solution I count 7! = 5,040 solutions. Trying 1e15 shuffles There are 15!/8! = 32,432,400 permutations of the set (and for that matter 15! is only about 1.3e12). I don't see mention in Algorithm::Permute of how it handles duplicate elements, but I know that Algorithm::Loops handles them correctly. That said I do agree with the thrust of your point. :)	[reply]
Re^8: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by karlgoethebier (Abbot) on Sep 24, 2023 at 17:45 UTC
Re^9: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by hv (Prior) on Sep 24, 2023 at 21:17 UTC
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Re^9: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by LanX (Saint) on Sep 24, 2023 at 18:05 UTC
Re^8: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by LanX (Saint) on Sep 24, 2023 at 17:42 UTC
Re^9: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by karlgoethebier (Abbot) on Sep 24, 2023 at 18:45 UTC
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Re^7: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by karlgoethebier (Abbot) on Sep 24, 2023 at 16:25 UTC
So this aren’t valid permutations? `karl@h3002993:~/src/perl$ ./pmute.pl 1 8 1 2 1 7 1 3 1 6 1 5 1 4 1 karl@h3002993:~/src/perl$ ./pmute.pl 1 3 1 4 1 7 1 5 1 2 1 6 1 8 1 karl@h3002993:~/src/perl$ ./pmute.pl 1 4 1 8 1 6 1 5 1 3 1 2 1 7 1 karl@h3002993:~/src/perl$ ./pmute.pl 1 5 1 8 1 2 1 4 1 6 1 3 1 7 1 karl@h3002993:~/src/perl$ ./pmute.pl 1 7 1 5 1 4 1 3 1 8 1 2 1 6 1` [download] FYI `karl@h3002993:~/src/perl$ time ./pmute.pl 1 4 1 3 1 2 1 6 1 5 1 7 1 8 1 real 0m0,081s user 0m0,076s sys 0m0,004s karl@h3002993:~/src/perl$ lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Address sizes: 46 bits physical, 48 bits virtual Byte Order: Little Endian CPU(s): 1 On-line CPU(s) list: 0 Vendor ID: GenuineIntel Model name: Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz …` [download] «The Crux of the Biscuit is the Apostrophe»	[reply] [d/l] [select]
Re^8: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by LanX (Saint) on Sep 24, 2023 at 17:49 UTC
Re^7: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by karlgoethebier (Abbot) on Sep 24, 2023 at 17:33 UTC
Somehow I also calculate differently: `CL-USER> (expt 10 15) 1000000000000000 CL-USER> (* 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15) 1307674368000` [download] «The Crux of the Biscuit is the Apostrophe»	[reply] [d/l]