r"""Separation to another pixel coordinate.

        This is the two-dimensional cartesian separation :math:`d` with

        .. math::
            d = \sqrt{(x_1 - x_2) ^ 2 + (y_1 - y_2) ^ 2}

        Parameters
        ----------
        other : `PixCoord`
            Other pixel coordinate

        Returns
        -------
        separation : `numpy.array`
            Separation in pixels

def separation(self, other):
        r"""Separation to another pixel coordinate.

        This is the two-dimensional cartesian separation :math:`d` with

        .. math::
            d = \sqrt{(x_1 - x_2) ^ 2 + (y_1 - y_2) ^ 2}

        Parameters
        ----------
        other : `PixCoord`
            Other pixel coordinate

        Returns
        -------
        separation : `numpy.array`
            Separation in pixels
        """
        dx = other.x - self.x
        dy = other.y - self.y
        return np.hypot(dx, dy)