replicant4 has asked for the wisdom of the Perl Monks concerning the following question:

thanks again ikegami and all for your help. I am a beginner at perl so I 've been trying to answer my questons, but it was no good. I have another one for you, which might be a bit trickier. I need to calculate the frequencies by which specific combinations appear. So after I do the pairwise combinations and store them into the @count _collection(that is all the possible times that specific combinations appear, then I have to do that for individual sites and calculate the frequency. In the code that is if a divide a specific counter (say counterAG) from %counts with how many times it appears in the AoH. That is I need to calulate countAG/total_count_AG. I don't know if this is possible, I suspect that since the keys of the hashes are similar, it can be done, but I am not sure how. Once again thanks for your patience and your time.
use strict; use warnings; my @site1 = qw( AATKKM AKTKKM ); my @site2 = qw( GGGGGG HHHHHH ); my $site1; my $site2; my @pairs; my @count_collection; foreach $site1 (@site1) { my @site1_parts = split(//, $site1); my %counts; foreach $site2 (@site2) { my @site2_parts = split(//, $site2); my $i = @site1_parts; $counts{$site1_parts[$i].$site2_parts[$i]}++ while ($i--); } push(@count_collection, \%counts); } foreach (@count_collection) { my $counts = $_; print($_, ': ', $counts->{$_}, $/) foreach (sort keys %$counts); print($/); } __END__ output ====== AG: 2 AH: 2 KG: 2 KH: 2 MG: 1 MH: 1 TG: 1 TH: 1 AG: 1 AH: 1 KG: 3 KH: 3 MG: 1 MH: 1 TG: 1 TH: 1

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Re: again regarding pairwise comparisons between strings and arrays
by Roy Johnson (Monsignor) on Oct 21, 2004 at 17:14 UTC
    All you need to do is keep a global count of each combination, right?
    my %total_count; foreach $site1 (@site1) { my @site1_parts = split(//, $site1); my %counts; foreach $site2 (@site2) { my @site2_parts = split(//, $site2); for my $i (0..$#site1_parts) { $counts{$site1_parts[$i].$site2_parts[$i]}++; $total_count{$site1_parts[$i].$site2_parts[$i]}++; } } push(@count_collection, \%counts); } foreach my $counts (@count_collection) { foreach (sort keys %$counts) { print($_, ': ', "$counts->{$_}/$total_count{$_}", $/); } print($/); }

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