it's hard to give you a good solution without knowing what format you're storing your array in.

Anyway the following does all you ask for, and was inspired by your first response. I would point out that slurping data like this gives funny x,y coordinates when accessing elements from the array (but makes it easy to slurp and pring), eg... 

$arr[y][x_from_top]

[download]
here's the full code... 
#!/usr/bin/perl -w

my @matrix1;
while (<DATA>) {
    push @matrix1, [ split(/\s+/) ];
}

my @matrix2 = empty_matrix(35,35);
overwrite_matrix(\@matrix2, \@matrix1, 0, 0);

print get_matrix(\@matrix1);
print "\n";
print get_matrix(\@matrix2);


#==============================================================
sub empty_matrix { map {[ map{0}(1..$_[1]) ]} (1..$_[0]) }
#==============================================================
sub get_matrix { join("\n", map { join(",", @$_) } @{$_[0]}    ) }
#==============================================================
sub overwrite_matrix {
    my ($array_ref1, $array_ref2, $x_offset, $y_offset) = @_;
    my $y = 0;
    foreach my $row_ref (@$array_ref2) {
        my $x = 0;
        foreach my $value (@$row_ref) {
            $array_ref1->[$y + $y_offset][$x + $x_offset] = $value;
            $x++;
        }
        $y++;
    }
}


__DATA__
2.8017  0        0        0        0        0        0
0        1.2969    0        0        0        0        0
0        0        0.5495    0        0        0        0
0        0        0        0.2329    0        0        0
0        0        0        0        0.1953    0        0
0        0        0        0        0        0.1723    0
0        0        0        0        0        0        0.0959

[download]
---
my name's not Keith, and I'm not reasonable.

In reply to Re: expanding a PDL matrix by reasonablekeith
in thread expanding a PDL matrix by Angharad

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