hdpmodel.py 文件源码

def expect_log_sticks(sticks):
    """
    For stick-breaking hdp, return the E[log(sticks)]
    """
    dig_sum = sp.psi(np.sum(sticks, 0))
    ElogW = sp.psi(sticks[0]) - dig_sum
    Elog1_W = sp.psi(sticks[1]) - dig_sum

    n = len(sticks[0]) + 1
    Elogsticks = np.zeros(n)
    Elogsticks[0: n - 1] = ElogW
    Elogsticks[1:] = Elogsticks[1:] + np.cumsum(Elog1_W)
    return Elogsticks