Now another problem If you have a hash with multiple values for each key such as the following. How would you calculate the max for each key: Example 

Keys    value
A       1
A       2
A       3
B       4
B       5
B       6

[download]

use strict;
use warnings;
use List::Util qw(first max);

while(<INPUT2>){
         (my $probeset_id, my $origin, my $probeseq, my $pip, my $gc, 
+my $affyscore) = split("\t", $_);

         push (@{$hash_F2_1{$origin}}, $pip); # This makes a hash of m
+ultiple value for each probeset ID

foreach my $origin (sort keys %hash_F2_1){
    foreach my $position (@{$hash_F2_1{$origin}}){

         my $max = max values %hash_F2_1;
         print "$origin\t$max\n";
     }
}

[download]
THIS CODE DOES NOT WORK!! Any Idea

In reply to Re^4: max value in a hash by sesemin
in thread max value in a hash by rsiedl

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