Why not keep the fragments as pairs. The pairs can then combine to produce four alternatives.

1 => [ 'TTAAGTAGCATCGATTTATAGCATCGACTAGTAA', 'TTACTAGTCGATGCTATAAATCGA +TGCTACTTAA' ], 2 => [ ... ]

Or, you could keep only the F fragments, but assemble the four FF FR RF RR variants right as you combine two fragments. For example, write a sub that accepts two keys and returns four pairs as a list. Breaking down the problem into subroutines is a smart idea in any case. Using Algorithm::Combinatorics combinations() is then possible since you have one key per fragment/cognate.


In reply to Re: Obtaining combinations of hash keys and values by Anonymous Monk
in thread Obtaining combinations of hash keys and values by Anonymous Monk

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