log_normal_cascade.py

def lognormal_cascade(k, v,ln_lambda, ln_theta):

    k = k - 1

    m0 = np.random.lognormal(ln_lambda,ln_theta)
    m1 = np.random.lognormal(ln_lambda,ln_theta)
    M = [m0, m1]

    if (k >= 0):
        d=[0 for x in range(0,2)]
        for i in range(0,2):
            d[i] = lognormal_cascade(k, (M[i]*v), ln_lambda, ln_theta)

        v = d

    return v