计算七类窗函数并给出归一化对数幅频曲线，同时也是利用窗函数法设计FIR滤波器的程序MDEFIR1所调用的子程序MWINDOW.C-Calculation of seven types of window function and gives the normalized logarithmic amplitude-frequency curve, but also use a window function method FIR filter design procedures MDEFIR1