hi, I am a beginner for perl. So forgive mysilly problem. 
#!/usr/bin/perl -w
use strict;

my %myhash=();
my $myhash;

sub do_hash {
    my ($filename)=@_;
    open(FH, $filename) or die "Can't open $filename: $!\n";

    while(<FH>){
        chomp;          
    my ($Name, $Data)=split/\t/;  
}
    close FH;
}

open(DATA_LIST, "<data_list") or die "Can't open data_list to read!: $
+!\n";
while (<DATA_LIST>){
        
     chomp;
     my ($Line,$Filed,$Dvalue)=split/\t/;

#open(MYHASH, ">myhash") or die "Can't open myhash to write : $!\n"; 
do_hash("file_data");
           
     print $myhash{$Line},"\n"; 

     if (exists $myhash{$Line}){

        print $Filed,"\t ",$Dvalue,"\t",  $myhash{$Line},"\n"; 

      }
}

[download]

When I run it, it tell me:
Use of uninitialized value at ./dsilklx line 51.which is:
print $myhash{$Line},"\n";
if I use:
 print $myhash{a123},"\n"; instead(al23 is one of the $Line value), it print out the whole value correctlly. It print out $Line, $Filed and $Dvalue correctlly too. What is the problem? Please help!

Edit kudra, 2002-05-22 Changed title, fixed code tags

In reply to uninitialized value on hash lookup (was: hash problem) by Anonymous Monk

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