#!/usr/local/bin/cz -- use b num Fc, Fd, dt, t1 num message(num t) return sin(3 * 2*pi*t) Main() paper(1024, 500) Fc = 20 Fd = 10 t1 = 1 dt = t1 / w num integral_m = 0 # initial value for(t, 0.0, t1, dt) num m = message(t) integral_m += m * dt # simplest numerical integration num y = cos(2*pi*(Fc*t + Fd*integral_m)) curve(t * w/t1 - w_2, y * h_2 / 2) Paint()