@staticmethod
def fit_deriv(mag, phi_star, m_star, alpha):
    '\n        Schechter luminosity function derivative with respect to\n        parameters.\n        '
    if (isinstance(mag, Quantity) or isinstance(m_star, Quantity)):
        raise ValueError('mag and m_star must not have units')
    factor = (10 ** (0.4 * (m_star - mag)))
    d_phi_star = (((0.4 * np.log(10)) * (factor ** (alpha + 1))) * np.exp((- factor)))
    func = (phi_star * d_phi_star)
    d_m_star = (((((alpha + 1) * 0.4) * np.log(10)) * func) - (((0.4 * np.log(10)) * func) * factor))
    d_alpha = (func * np.log(factor))
    return [d_phi_star, d_m_star, d_alpha]
Schechter luminosity function derivative with respect to
parameters.
@staticmethod
def fit_deriv(mag, phi_star, m_star, alpha):
    '\n        Schechter luminosity function derivative with respect to\n        parameters.\n        '
    if (isinstance(mag, Quantity) or isinstance(m_star, Quantity)):
        raise ValueError('mag and m_star must not have units')
    factor = (10 ** (0.4 * (m_star - mag)))
    d_phi_star = (((0.4 * np.log(10)) * (factor ** (alpha + 1))) * np.exp((- factor)))
    func = (phi_star * d_phi_star)
    d_m_star = (((((alpha + 1) * 0.4) * np.log(10)) * func) - (((0.4 * np.log(10)) * func) * factor))
    d_alpha = (func * np.log(factor))
    return [d_phi_star, d_m_star, d_alpha]