说明：  求出laguerre滤波器的分子分母系数，绘出其幅频响应图并与FIR滤波器作比较。该程序为19阶Laguerre低通滤波器和22阶带通滤波器
(obtained laguerre filter coefficient of molecular denominator, chart its amplitude frequency response plans with the FIR filter for comparison. The procedure for the 19-Laguerre low-pass filter and 22 band pass filter)