push @multi_array, [split(/,\s*/, $_)] for <DATA>;

##</code><code>##

foreach my $row (@multi_array) {
    s/^\s+// foreach (@$row);
}

##</code><code>##

# modify columns
($_->[0] *= 1.0, $_->[1] /= 1.0) for @multi_array;

##</code><code>##

for my $row (@multi_array) {
    $row->[0] *= 1.0;
    $row->[1] /= 1.0;
}

##</code><code>##

foreach my $row (@multi_array) {
    foreach my $item (@$row) {
        $item =~ s/^\s+//;
    }
}