def function(self, x, y, amp, e1, e2, s_scale, center_x=0, center_y=0):
        """

        :param x:
        :param y:
        :param theta_E:
        :param e1:
        :param e2:
        :param s_scale:
        :param center_x:
        :param center_y:
        :return:
        """
        phi_G, q = param_util.ellipticity2phi_q(e1, e2)
        # shift
        x_ = x - center_x
        y_ = y - center_y
        # rotate
        x__, y__ = util.rotate(x_, y_, phi_G)
        # evaluate
        f_ = self._nie_simple_function(x__, y__, amp, s_scale, q)
        # rotate back
        return f_
def function ( self , x , y , amp , e1 , e2 , s_scale , center_x = 0 , center_y = 0 ) : phi_G , q = param_util . ellipticity2phi_q ( e1 , e2 ) x_ = x - center_x y_ = y - center_y x__ , y__ = util . rotate ( x_ , y_ , phi_G ) f_ = self . _nie_simple_function ( x__ , y__ , amp , s_scale , q ) return f_
:param x:
        :param y:
        :param theta_E:
        :param e1:
        :param e2:
        :param s_scale:
        :param center_x:
        :param center_y:
        :return: