utils.py 文件源码

def beta_expectation(a, b, k):
    mysum = psi(a + b)
    Elog_a = psi(a) - mysum
    Elog_b = psi(b) - mysum
    Elog_beta = n.zeros(k)
    Elog_beta[0] = Elog_a[0]
    # print Elog_beta
    for i in range(1, k):
        Elog_beta[i] = Elog_a[i] + n.sum(Elog_b[0:i])
        # print Elog_beta
    # print Elog_beta
    return Elog_beta