getE-scan

#!/usr/bin/perl

if (@ARGV < 2) { die "Syntax: getE-scan filename identifier [nstates]\nPulls all the optimised energies out of a PES scan.\nidentifier is anything that will pull out the value of the parameter being scanned.\nUse nstates to pull out more than one excited state and calculate actual energies for TD-DFT PES scans.\n" } 

$file = $ARGV[0];
$id = $ARGV[1];
$nstates = $ARGV[2];
$read = "n";
$npt = 0;

open (FILE, "<$file") || die "couldn't open $file for reading\n";
while ($line = <FILE>) {
 #   print "$line $read\n";
     if ($line =~ / Optimization completed./) { 
         $read = "y";
         printf "%-3i   ", $npt;
     } 
     if (($line =~ /$id/) && ($line =~ /-DE\/DX/) && ($read =~ /y/))  { 
         @tmp = split(/\s+/,$line);
         if ($tmp[3] =~/\d+\.\d+/) {
             $r[$npt] = $tmp[3];
         }
         else {
             $r[$npt] = $tmp[4];
         }
         printf "%6.4f   ", $r[$npt];
         if ($nstates == 0) { 
             printf "%12.6f    ", $E[$npt][0];
             $npt++;
             $read = "n";
             print "\n";
         }
     }
     if ($line =~ /SCF Done/)  { 
         @tmp = split(/\s+/,$line);
         $E[$npt][0] = $tmp[5];
     }
     if (($line =~ / Excited State/) && ($read =~ /y/))  { 
         for ($i = 1; $i <= $nstates-1; $i++) {
             if ($line =~ / Excited State   $i/) {
                 @tmp = split(/\s+/,$line);
                 $E[$npt][$i] = $E[$npt][0] + $tmp[5]/27.211;
                 printf "%12.6f    ", $E[$npt][0];
                 printf "%12.6f    ", $E[$npt][$i];
             }
         }
     }
     if (($line =~ / Excited State   $nstates/) && ($read =~ /y/))  { 
         @tmp = split(/\s+/,$line);
         $E[$npt][$nstates] = $E[$npt][0] + $tmp[5]/27.211;
         printf "%12.6f    ", $E[$npt][0];
         printf "%12.6f    ", $E[$npt][$nstates];
         $npt++;
         $read = "n";
         print "\n";
     }
}

close (FILE);