sub fp_equal {
        my ($X, $Y, $POINTS) = @_;
        my ($tX, $tY);
        $tX = sprintf("%.${POINTS}g", $X);
        $tY = sprintf("%.${POINTS}g", $Y);
        return $tX eq $tY;
    }

    fp_equal($x, $y, 3);

##</code><code>##

    sub fp_equal {
        return abs($_[0] - $_[1]) < $_[2];
    }

    fp_equal($x, $y, 0.001);