如果题中给出了一个系统的系统函数，那你就可以求出它的零、极点，根据题中给出的系数不同，你改变a，b的值，就能求出相应的零、极点值，此程序只是个样题-If the problem is given in a system of system function, then you can find it is zero, pole, according to the different coefficients given topic, you change a, b values, we can