calculate Debye temperature for constant q

    :param v: unit-cell volume in A^3
    :param v0: unit-cell volume in A^3 at 1 bar
    :param gamma0: Gruneisen parameter at 1 bar
    :param q: logarithmic derivative of Gruneisen parameter
    :param theta0: Debye temperature at 1 bar
    :return: Debye temperature in K

def constq_debyetemp(v, v0, gamma0, q, theta0):
    """
    calculate Debye temperature for constant q

    :param v: unit-cell volume in A^3
    :param v0: unit-cell volume in A^3 at 1 bar
    :param gamma0: Gruneisen parameter at 1 bar
    :param q: logarithmic derivative of Gruneisen parameter
    :param theta0: Debye temperature at 1 bar
    :return: Debye temperature in K
    """
    gamma = constq_grun(v, v0, gamma0, q)
    if isuncertainties([v, v0, gamma0, q, theta0]):
        theta = theta0 * unp.exp((gamma0 - gamma) / q)
    else:
        theta = theta0 * np.exp((gamma0 - gamma) / q)
    return theta