in reply to creating matrices for PDL module

May I recommend an editor (other than notepad) which may have improved indenting facilities?

The syntax error is your friend, if it tells you that ]; is bad, then it probably is. If not, then something near it is.

If you were to indent your code in a more clear fashion your code might look like this:

#!/usr/bin/perl -w

use PDL;

$matrixfile = $ARGV[0];

open(MATRIX, "$matrixfile") ||
  die "Error: Can't open $matrixfile file for reading: $!\n";

@matrix = <MATRIX>;

for(my $i = 0; $i < @matrix; $i ++)
{
    $a = substr($matrix[$i], 0, 5);
    $b = substr($matrix[$i], 6, 5);
    $c = substr($matrix[$i], 12, 5);
    $d = substr($matrix[$i], 18, 5);
    $cd = substr($matrix[$i], 24, 5);
    
    my $dmat = pdl [
                    [ $a, $b, $c, $d],
                    
                }

    ];

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Instantly you'd see that maybe a closing bracket was missing off the my $dmat = pdl [ ... ]; command. And that the final curly brace should probably be swapped with the square bracket the syntax error is complaining about.

Update: posted solution here:

#!/usr/bin/perl -w
use PDL;

$matrixfile = $ARGV[0];

open(MATRIX, "$matrixfile") ||
  die "Error: Can't open $matrixfile file for reading: $!\n";

@matrix = <MATRIX>;

for(my $i = 0; $i < @matrix; $i ++)
{
    $a = substr($matrix[$i], 0, 5);
    $b = substr($matrix[$i], 6, 5);
    $c = substr($matrix[$i], 12, 5);
    $d = substr($matrix[$i], 18, 5);
    $cd = substr($matrix[$i], 24, 5);
    
    my $dmat = pdl [
                    [ $a, $b, $c, $d],
                    ]
};

[download]

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