Assuming the same number of fields on every row of the data file, 

my @data;
while (<>) {
   my @fields = split ' ';
   for my $row (0..$#fields) {
      push @{$data[$row]}, $fields[$row];
   }
}

[download]

Tested.

In reply to Re: How to swap rows with columns? by ikegami
in thread How to swap rows with columns? by perl_geek

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