def in_domain(self, points):
        """
        Returns ``True`` if all of the given points are in the domain,
        ``False`` otherwise.

        :param np.ndarray points: An `np.ndarray` of type `self.dtype`.

        :rtype: `bool`
        """
        if np.all(np.isreal(points)):
            are_greater = np.all(np.greater_equal(points, self._min))
            are_smaller = np.all(np.less_equal(points, self._max))
            return  are_greater and are_smaller
        else:
            return False