def model(self, a, x0, y0, sx, sy, theta, b, beta):
    dx_ = (self.x - x0)
    dy_ = (self.y - y0)
    dx = ((dx_ * np.cos(theta)) + (dy_ * np.sin(theta)))
    dy = (((- dx_) * np.sin(theta)) + (dy_ * np.cos(theta)))
    return (b + (a / np.power(((1 + ((dx / sx) ** 2)) + ((dy / sy) ** 2)), beta)))
def model(self, a, x0, y0, sx, sy, theta, b, beta):
    dx_ = (self.x - x0)
    dy_ = (self.y - y0)
    dx = ((dx_ * np.cos(theta)) + (dy_ * np.sin(theta)))
    dy = (((- dx_) * np.sin(theta)) + (dy_ * np.cos(theta)))
    return (b + (a / np.power(((1 + ((dx / sx) ** 2)) + ((dy / sy) ** 2)), beta)))