Hi. I'm trying to write what is probably a simple perl script to create five matrices (I want to be able to calculate the determinants for each matrix using PDL's determinant() function).
I have a text file which looks like this. 

4     2     9     7     21     
2     5     4     4     11.5 
6     3     5     3     15.5 
8     4     6     6     22

[download]

And I want to be able to create five matrices like this from the text file. 

my $dmat = pdl [
           [4, 2, 9, 7],
           [2, 5, 5, 4],
           [6, 3, 5, 3],
           [8, 4, 6, 6],
           ];

my $damat = pdl [
           [21, 2, 9, 7],
           [11.5, 5, 5, 4],
           [15.5, 3, 5, 3],
           [22, 4, 6, 6],
           ];

my $dbmat = pdl [
           [4, 21, 9, 7],
           [2, 11.5, 5, 4],
           [6, 15.5, 5, 3],
           [8, 22, 6, 6],
           ];

my $dcmat = pdl [
           [4, 2, 21, 7],
           [2, 5, 11.5, 4],
           [6, 3, 15.5, 3],
           [8, 4, 22, 6],
           ];

my $ddmat = pdl [
           [4, 2, 9, 21],
           [2, 5, 5, 11.5],
           [6, 3, 5, 15.5],
           [8, 4, 6, 22],
           ];

[download]

This is what I have managed so far. Right now I'm working on creating the first matrix only. 

#!/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]

But of course it doesn't work, it comes up with a syntax error ... because the last ]; is in the 'wrong' place .. but I need it 'there' so to speak to mark the end of the matrix if you see what I mean. Could anyone please point me in the right direction? Thanks.

READMORE tags added by Arunbear

In reply to creating matrices for PDL module by Angharad

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