in reply to How to add missing part in a Hash of Array
I suspect that we have all misunderstood your data structure. The only code that you provided does indeed reference a "hash of arrays". It associates an array consisting of one position and the name of one amino acid with each protein. (All the responses so far assume that you hve an array of these arrays for each protein). It would be easier to work with a hash of hashes which associates an amino acid with its protein and its position.
Bill
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