#!/usr/bin/perl
#

  
  my($output_file, $term_options);

  # get the arguments
  $output_file = "bb_lam_a.ps";
  $term_options = "postscript color enhanced 'Helvetica,18' ";

  $cmdfile = "gnuplot.in";
  
  open (CMDFILE, ">$cmdfile") || die("can't open $cmdfile for writing");
  printf CMDFILE "set output '$output_file' \n";
  printf CMDFILE "set term $term_options \n";
  printf CMDFILE "set grid \n";
  printf CMDFILE "set key top right \n";
  printf CMDFILE "set logscale x \n";
  printf CMDFILE "set ylabel 'Intensity (arb units)' \n";
  printf CMDFILE "set xlabel 'Wavelength (m)' \n";
  printf CMDFILE "set title 'Blackbody radiation '\n";
  
  $cmd = "plot [1E-8:1E-2][5:30]  'bb_lam_1000.dat' using (10.0**\$1):(\$4) ";
  $cmd .=  "  with lines  lt 1 lw 5 t '1000 K' ";
  $cmd = $cmd . ", 'bb_lam_2000.dat' using (10.0**\$1):(\$4) ";
  $cmd .= "   with lines  lt 2 lw 5 t '2000 K'";
  $cmd = $cmd . ", 'bb_lam_3000.dat' using (10.0**\$1):(\$4) ";
  $cmd .= "   with lines  lt 3 lw 5 t '3000 K'";

  printf CMDFILE "$cmd \n";
  printf CMDFILE "set output \n";
  printf CMDFILE "quit \n";
  close(CMDFILE) ;
  
  $retval = `gnuplot < $cmdfile`;
  printf "retval is ..%s..\n", $retval;
  
  if ($term_options =~ /postscript/) {
    $psfile = $output_file;
    $giffile = $psfile;
    $giffile =~ s/.ps/.png/;
    $cmd = "convert -rotate 90 $psfile $giffile";
    printf "cmd is ..$cmd.. \n";
    $ret = `$cmd`;
  }

exit 0;
