Searching for information taken from one file in another file is quite a common task. The usual solution is to hash the identifiers, then iterate over the second file and check the hash for the existence of the identifier.

In your case, you have to change the identifiers, as the underscore in contig names is not present in the genbank: 

#!/usr/bin/perl
use warnings;
use strict;

my %contig;
open my $CNTG, '<', 'contig_names' or die $!;
while (<$CNTG>) {
    chomp;
    s/_//;  # Remove the underscore, as it doesn't appear in the genba
+nk.
    $contig{$_} = 1;
}

local $/ = '//';  # Read the file one record a time.
open my $GB, '<', 'genbank' or die $!;
while (<$GB>) {
    if (my ($id) = /LOCUS \s+ \S+ _ (contig [0-9]+)/x) {
        print if $contig{$id};
    }
}

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لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: How do i extract only contigs of interest by choroba
in thread How do i extract only contigs of interest by faozhi

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