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Re: Generating Repeatable Pseudorandom Sequencesby Abigail-II (Bishop) |
on Sep 05, 2002 at 16:51 UTC ( [id://195439]=note: print w/replies, xml ) | Need Help?? |
Calling srand more than once is not recommended,
but that doesn't mean the results are always bad. It depends a bit
on the needs of the rest of the program, but you might be able
to call srand with a known seed just before you
sort, and after the sort, you call srand without
an argument.
But there's a totally different approach. If you need to shuffle an array using the same permutation multiple times, instead of playing games by seeding a PRN generator with the same seed, you could just shuffle the numbers 0 .. $#array and remember them (say, in an array @perm_indices). Then, if you need to shuffle an array again, you do:
You may be able to use the Memoize module to this storing for you. Abigail
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