Is there a VERY fast (maybe implemented in C) way to calculate intersection and union on two arrays?
You may want to have a look at PDL. And, no doubt, the fastest routines have probably been written in the early 60s, in FORTRAN. But I wouldn't know how to link FORTRAN routines to perl.

In reply to Re: Fast, Efficient Union and Intersection on arrays by JavaFan
in thread Fast, Efficient Union and Intersection on arrays by barvin

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