I'm assuming every line contains data and that the files are in tab delimited format. 
use strict;

my @file1 = (
    "complex.1\t1.356\n",
    "complex.2\t1.879\n",
);
my @file2 = (
    "12.02\t/home/complex.2out\n",
    "10.25\t/home/complex.1out\n",
);

my (%hash, $ref, $values);
chomp(@file1); chomp(@file2);
foreach (@file1) {
    $_ =~ /^complex\.(\d+)\t([\d\.]+)$/;
    $hash{$1}->[0] = $2;
}
foreach (@file2) {
    $_ =~ /^([\d\.]+)\t\/home\/complex.(\d+)out$/;
    $hash{$2}->[1] = $1;
}
foreach (sort {$a <=> $b} keys %hash) {
    $ref = $hash{$_};
    $values = join("\t", @$ref);
    print "complex.$_\t$values\n";
}

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In reply to Re: How can I merge data using a hash? by TedPride
in thread How can I merge data using a hash? by Anonymous Monk

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