Hi All, I am trying to correlate two files together. Basically I am using the elements of the master file to look up the matching element in my index file and push the matching value into a new array. The thing is, it seems to run extremely slow. The files themselves are not overly huge, 30MB for the master file and 500MB for the index. I strongly suspect that this search could be done better and my logic is not quite right. Any idea to speed up this task is greatly appreciated. Thank you!

This is my code: 

my $index = 'path/to/file/file.name';
tie (@master, 'Tie::File', $masterList) or die "Can't tie $masterList"
+;

foreach my $pos(@master){
        chomp $pos;
        my $quickLook = qx(grep '^$pos' $index);
        my @split = split(/\t/,$quickLook);
        print $tFile $split[1];
         push (@idxArray, $split[1]);
 }

[download]
This is my Master data 
1
2
3
4
6
8
10
12
15
17
etc...
3000000

[download]
and this is my index data 
1  atc
2 gca
3 att
4 ggc
5 aaa
etc...
29000000 ttg

[download]

In reply to Better way to search an Array? by doubleqq

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