now it works but i have another question .. do you know why when i print data Dumper i donīt get anything? 
my $freqocurrence={};
sub freq_oc{
    foreach my $key (keys %$observation){
        $total10 += $observation->{$key};
    }


foreach my $key (keys %$observation){
    $freqocurrence->{$key} = $observation->{$key}/$total10;
    print "Frequency of ocurrence:     Aminoacid $key-> $freqocurrence
+->{$key}\n";
    
    }

}

print Dumper $freqocurrence;

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In reply to Re^2: Problem in a Loop by madM
in thread Problem in a Loop by madM

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