I've written a small perl script to create a series of .gif files, from a series of text datafiles, using PGPLOT. The code is shown below. It takes the 100 text files and turns them into 100 .gif images called 'frame_xxx.gif' from 001 to 100. These then form the frames of an animated gif.

The code sucessfully creates frame 1 and frames 3-100 as files in the $animdir directory (so it looks like its working), but for frame 2 it creates the gif file in the current directory with a filename of pgplot10922.gif and creates an empty frame_002.gif file in the $animdir directory. This is accompanied by the onscreen message "PGPLOT, Writing new GIF image as: pgplot10922.gif"

I'm very confused. This file is correct, but not called the right thing or in the right place! And why does it work for all the other frames but not that one? Any ideas?

# -------------- System variables
my $currentdir = getcwd();
my $logdir = "Logs";
my $outdir = "Windoutput";
my $specdir = "Specfiles";
my $animdir = "Animfiles";
# -------------- End system variables

# -------------- Main program variables
my $framenumber = 1;
my $frameplot;
my $emin=300;
my $emax=13000;
my $xmin = log10($emin/1000);
my $xmax = log10($emax/1000);
my $ymin = log10(6E2);
my $ymin2 = log10(2E4);
my $ymax = log10(6E6);
my $filename;

# -------------- Prompted Variables
print "  Please enter number of frames (default = 100): ";
my $nframes = <STDIN>;
chomp $nframes;
$nframes = 100 if ($nframes eq "");

print "  Processing frame:\n  ";

# -------------- Main program loop
until ($framenumber>$nframes)
{
    print "${framenumber}: ";
    $filename = "$animdir/frame_00${framenumber}.gif/gif" if ($framenu
+mber<10);
    $filename = "$animdir/frame_0${framenumber}.gif/gif" if (($framenu
+mber>9) and ($framenumber<100));
    $filename = "$animdir/frame_${framenumber}.gif/gif" if $framenumbe
+r>99;
    print "$filename\n";

    $frameplot = PDL::Graphics::PGPLOT::Window->new(Device => $filenam
+e, AxisColour => 'black', Font => 'Roman', WindowXSize => 8 , WindowY
+Size => 9.23, HardLW => 4);
    
    $frameplot = PDL::Graphics::PGPLOT::Window->new(Device => '/xs', A
+xisColour => 'black', Font => 'Roman', WindowXSize => 8 , WindowYSize
+ => 9.23) if ($debug_level==1);
    
    # Prepare space for transmitted spectrum plot
    $frameplot->env($xmin,$xmax,$ymin,$ymax,
    {
    PlotPosition => [0.06, 0.99, 0.06, 0.639],
    Charsize => 0.8,
    Axis => 'LogXY',
    Xtitle => 'Energy (keV)',
    Ytitle => 'E L\dE\u [erg(erg/s/erg)]',
    });

    my ($energy, $trans) = rcols "$animdir/${framenumber}_trans_spect.
+txt", {LINES => '4:-1'};
    my ($junk, $emit) = rcols "$animdir/${framenumber}_emit_spect.txt"
+, {LINES => '4:-1'};
    my ($incenergy, $inclumin) = rcols "${xscortpath}/powerlaw.dat", {
+LINES => '2:-1'};
    
    my $plotmask = which(($incenergy>$emin) & ($incenergy<$emax));
    my $x = $incenergy->dice($plotmask);
    my $y = $inclumin->dice($plotmask);
    $frameplot->line(log10($x/1000), log10($y*1.60217646E-12*$x), {Col
+our => 'black'});
    
    $plotmask = which(($energy>$emin) & ($energy<$emax));
    $x = $energy->dice($plotmask);
    $y = $trans->dice($plotmask);
    $frameplot->line(log10($x/1000), log10($y*1.60217646E-12*$x), {Col
+our => 'blue'});
    $y = $emit->dice($plotmask);
    $frameplot->line(log10($x/1000), log10($y*1.60217646E-12*$x), {Col
+our => 'red'});
    
    $frameplot->env($xmin,$xmax,$ymin2,$ymax,
    {
    PlotPosition => [0.06, 0.99, 0.639, 0.99],
    Charsize => 0.8,
    Axis => ['BCSTL','BCNSTL'],
    Ytitle => 'E L\dE\u [erg(erg/s/erg)]',
    });
    
    $plotmask = which(($incenergy>$emin) & ($incenergy<$emax));
    $x = $incenergy->dice($plotmask);
    $y = $inclumin->dice($plotmask);
    $frameplot->line(log10($x/1000), log10($y*1.60217646E-12*$x), {Col
+our => 'black'});
    $y = ($emit+$trans)->dice($plotmask);
    $frameplot->line(log10($x/1000), log10($y*1.60217646E-12*$x), {Col
+our => 'dark green'});
    if ($debug_level==1)
    {
        print "Press return to continue...";
        my $pause = <STDIN>;
    }
    $frameplot->close();
    $framenumber++;
}
[download]