Re: Merging larges files by columns

[lidden]

If think you want something like this. (untested)

open my $OUTFILE, ">", "outfile.csv" or die "oh noo: $!";
open my $IN1, "<", "infile1.csv" or die "bummer1: $!";
open my $IN2, "<", "infile2.csv" or die "bummer2: $!";

while (<$IN1>){
    chomp;
    print $OUTFILE $_;

    my $line2 =<$IN2>;
    chomp $line2;
    my @f = split/,/, $line2;
    print $OUTFILE ",$f[1]\n";
}

close $IN2 or die $!;
close $IN1 or die $!;
close $OUTFILE or die $!;

[Kc12349]

I was about to post my very similar code. I would point out that if you are new to perl and not set in your ways, try to use lexical file handles as in my example as opposed to barewords.

use autodie;

open (my $out, '>', 'outfile.csv');
open (my $in1, '<', 'infile1.csv');
open (my $in2, '<', 'infile2.csv');

while ( defined (my $line = <$in1>) )
{
   chomp $line;
   print {$out} $line;

   chomp(my $in2_line = <$in2>);
   my @f = split m/,/, $in2_line;
   print {$out} ',' . $f[1] . "\n";
}

close $in1;
close $in2;
close $out;