#!/usr/bin/perl
#
# perl wf2dists.pl wffile distfile factor

if (($#ARGV < 1) | ($#ARGV > 2))
{
   print "

     Usage: perl $0 wffile distfile [factor]

     This outputs to distfile distances corresponding to points in wffile.
     factor allows conversion to other units - what's printed is 
      the distance in the current units multiplied by factor.

";
   exit;
}

$wffile = $ARGV[0];
$distfile = $ARGV[1];

open (WF,"$wffile");
open (DIST,">$distfile");
$factor = 1;
if ($#ARGV >= 2)
{
    $factor = $ARGV[2];
}

while ($line = <WF>)
{
    ($x,$y,$z,@tmp) = split /\s+/, $line;
    $dist = sqrt ($x*$x + $y*$y + $z*$z) * $factor;
    print DIST "$dist\n";
}

close(DIST);
close(WF);