That doesn't work correctly.

You are jumping through a lot of contortions, seemingly to avoid explicitly opening files. That results in a lot of inefficiency; all that sorting could get expensive if the data sets are big. Using hashes for data that are already ordered and whose order you want to retain is a bad design decision.

And even with your comments, it's not particularly easy to read (for me; and I'm not new to Perl.)

The following might not win any style points, but it is straight forward and relatively efficient. And working. 

 
my $header;

# Handle the first file separately so we can keep the "categories."
my $file = shift;
$header = "CATS \t$file"; # CATS is category column header.
open my $fh, '<', $file or die "$file: $!";
my @lines = <$fh>;
close $fh;
chomp(@lines);

for my $file (@ARGV) {
    # Add filename to header.
    $header .= "\t$file";

    open my $fh, '<', $file or die "$file: $!";

    # Iterate through file
    my $i = 0;
    while (my $line = <$fh>) {
        chomp $line;
        # Append tab and 2nd column to appropriate line.
        $lines[$i++] .= "\t" . (split /\t/, $line)[1];
    }
    close $fh;
}
# print our header and each of our new lines.
print $header, "\n";
print "$_\n" for @lines;

[download]

-sauoq
"My two cents aren't worth a dime.";

In reply to Re^2: simple table join script by sauoq
in thread simple table join script by slavailn

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