This is something where very idiomatic "perlish" solutions exist, like:

  # open the file
  open my $fh, '<', 'myfile.dat' or die "$!"

  # translate the data into a 2D array
  my @rows = map [ split /\s+/ ],  <$fh>;

  # sort on any column
  my @sorted = sort { $a->[1] cmp $b->[1] } @rows;

  # print the result
  print "@$_\n" for @sorted;
[download]

I think this will do it here. As in Re: How to sort? noted, this doesn't look like a real "csv" data file.

Regards

mwa