public static function mul($z, $w) {
        if (!($z instanceof Complex)) $z = static::parse($z);
        if (!($w instanceof Complex)) $w = static::parse($w);

        return static::create($z->x * $w->x - $z->y * $w->y, $z->x * $w->y + $z->y * $w->x);
    }
public static function mul($z, $w) {
        if (!($z instanceof Complex)) $z = static::parse($z);
        if (!($w instanceof Complex)) $w = static::parse($w);

        return static::create($z->x * $w->x - $z->y * $w->y, $z->x * $w->y + $z->y * $w->x);
    }
public static function mul ( $ z , $ w ) { if ( ! ( $ z instanceof Complex ) ) $ z = static :: parse ( $ z ) ; if ( ! ( $ w instanceof Complex ) ) $ w = static :: parse ( $ w ) ; return static :: create ( $ z -> x * $ w -> x - $ z -> y * $ w -> y , $ z -> x * $ w -> y + $ z -> y * $ w -> x ) ; }
multiply two complex numbers

Complex::mul($z, $w) computes and returns $z*$w


@param mixed $z (Complex, or parsable to Complex)
@param mixed $w (Complex, or parsable to Complex)
@retval Complex
multiply two complex numbers