#!/usr/bin/perl -w

open(MATRIX, "matrixfile.dat") || die "Error: Can't open matrixfile fi
+le for reading: $!\n";


$i=0;
while ($spool = <MATRIX>) {
    chomp($spool);
    @arr = split(/ /,$spool);
    for ($x=0;$x<= $#arr;$x++) { $matrix[$i][$x] = $arr[$x];}
    $i++;
} # end while

$x=$x-1;
for ($j=0;$j<$i;$j++) {
    for ($r=0;$r<4;$r++)
    {
        print "[ ";
        $cntr=0;$c=$j;
        for($cntr=0;$cntr<4;$cntr++) 
        {
            if($c gt  $x) {
                $c=0;
            }
            print " $matrix[$r][$c]  " ;
            
            $c++;
        }
        print " ] \n";
    }
    print "\n";
}
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Have you typed M-x perl-mode, selected all your text (perhaps using cua-mode) and typed in M-x indent-region?