使用matlab进行IIR与FIR数字滤波器的设计。使用直接法和双线性变换法设计IIR数字滤波器，利用窗函数法，频率采用法设计FIR数字滤波器并进行GUI界面的设计。

-Using matlab to design IIR and FIR digital filter. Using the direct method and the bilinear transform to design IIR digital filter and using window function method, frequency sampling method to design FIR digital filter .Finally a GUI interface is designed to show the process .