Hi holli ... I have resolved many errors after using
"strict" and use "warnings". I am now getting this error message. Can you help me
understand this error 
use of uninitialized value in exists at sample.pl line 33, <FD> line 6
+.
use of initialized value in concatenation (.) or string at line 34 <FD
+> line 6
KEY in file 1 not found in file 2

[download]
Here is the updated code:- 
#!/usr/bin/perl

use warnings;
use strict;

my $fh1 = "File1.txt";
my $fh2 = "File2.txt";

open(FH, "$fh1") || die ("Can't open: $!");
my @AoH;
while ( <FH> ) {
              push @AoH, { split /[\s]+/ };
              }

my %sequences;
{
   open(FD, "$fh2") || die("Cannot open: $!");

   my $key;
   while (<FD>) {
       if ( s/^>// ) {
           $key = ( split /\|/ )[1];
       }
       else {
           chomp;
           $sequences{$key} .= $_;
       }
   }
}
for my $href ( @AoH ) {
  for my $role ( sort keys %$href ) {
                     my $key;
    if ( ! exists $sequences{$key} ) {
        warn "KEY $key in File1 not found in File2\n";
        next;
    }
    if ( length( $sequences{$key} ) < $href->{$role} ) {
        warn "KEY $key: File2 string length too short for File1 positi
+on value\n";
        next;
    }
    my $index = rindex( $sequences{$key}, "TTT", $href->{$role} );
    if ( $index < 0 ) {
        warn sprintf( "KEY %s: No TTT in File2 string prior to positio
+n %d\n",
                      $key, $href->{$role} );
        next;
    }
    $index += 3 while ( ($index + 3) < $href->{$role} );
    print "$key $href->{$role} " . substr($sequences{$key}, $index, 3)
+ . "\n";
}

}

[download]

In reply to Re^2: howto accomodate multiple values by aspirado
in thread howto accomodate multiple values by aspirado

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