My favorite solution is: 
sub commify
  {
    my $text = reverse $_[0];
    $text =~ s/(\d\d\d)(?=\d)(?!\d*\.)/$1,/g;
    return scalar reverse $text;
  }

[download]
 I regret wasting the node; i see Grandfather beat me to this solution...

In reply to Re: formatting numbers by apl
in thread formatting numbers by Anonymous Monk

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