ATOM   1279 C    ALA    81      -1.925 -11.270   1.404
ATOM   1280 O    ALA    81      -0.279   9.355  15.557
ATOM   1281 OXT  ALA    81      -2.188  10.341  15.346
TER   
ATOM   1282 N    THR    82      29.632   5.205   5.525
ATOM   1283 H1   THR    82      30.175   4.389   5.768
ATOM   1284 H2   THR    82      28.816   4.910   5.008
<code>
The code is: In the end it finds the maximum distance and its co ordinates
<code>
my @points = (); 
open(IN, @ARGV[0]) or die "$!"; 
while (my $line = <IN>) { 

  chomp($line); 
  my @array = (split (/\s+/, $line))[5, 6, 7]; 
  print "@array\n"; 
  push @points, [ @array ]; 
} 
close(IN); 


 $max=0;
 for my $i1 ( 0 .. $#points  )

{ 
    my ( $x1, $y1, $z1 ) = @{ $points[$i1] };  
    my $dist = sqrt( ($x1+1.925)**2 + ($y1+11.270)**2 + ($z1-1.404)**2 ); 
    print "distance from (-1.925 -11.270 1.404) to ( $x1, $y1, $z1 ) is $dist\n"; 

    if ( $dist > $max )
     { $max = $dist;
       $x=$x1;
       $y=$y1;
       $z=$z1; 
      }}
    print "maximum value is : $max\n";
print "co ordinates are : $x $y $z\n";