作业帮请问,滤波后如何出图呢?是否用需用反傅里叶变化?freq_sig1=fft(quake_data(:,4)); lfreq=length(freq_sig1); nyq=50; half_lfreq=floor(lfreq/2); freq=[1:1:(half_lfreq)]/(half_lfreq)*nyq posfreq=abs(freq_sig1); figureplot(freq,posfreq(1:h
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/06 05:52:30
![请问,滤波后如何出图呢?是否用需用反傅里叶变化?freq_sig1=fft(quake_data(:,4)); lfreq=length(freq_sig1); nyq=50; half_lfreq=floor(lfreq/2); freq=[1:1:(half_lfreq)]/(half_lfreq)*nyq posfreq=abs(freq_sig1); figureplot(freq,posfreq(1:h](/uploads/image/z/13944840-24-0.jpg?t=%E8%AF%B7%E9%97%AE%2C%E6%BB%A4%E6%B3%A2%E5%90%8E%E5%A6%82%E4%BD%95%E5%87%BA%E5%9B%BE%E5%91%A2%3F%E6%98%AF%E5%90%A6%E7%94%A8%E9%9C%80%E7%94%A8%E5%8F%8D%E5%82%85%E9%87%8C%E5%8F%B6%E5%8F%98%E5%8C%96%3Ffreq_sig1%3Dfft%28quake_data%28%3A%2C4%29%29%3B+lfreq%3Dlength%28freq_sig1%29%3B+nyq%3D50%3B+half_lfreq%3Dfloor%28lfreq%2F2%29%3B+freq%3D%5B1%3A1%3A%28half_lfreq%29%5D%2F%28half_lfreq%29%2Anyq+posfreq%3Dabs%28freq_sig1%29%3B+figureplot%28freq%2Cposfreq%281%3Ah)
请问,滤波后如何出图呢?是否用需用反傅里叶变化?freq_sig1=fft(quake_data(:,4)); lfreq=length(freq_sig1); nyq=50; half_lfreq=floor(lfreq/2); freq=[1:1:(half_lfreq)]/(half_lfreq)*nyq posfreq=abs(freq_sig1); figureplot(freq,posfreq(1:h
请问,滤波后如何出图呢?是否用需用反傅里叶变化?
freq_sig1=fft(quake_data(:,4));
lfreq=length(freq_sig1);
nyq=50;
half_lfreq=floor(lfreq/2);
freq=[1:1:(half_lfreq)]/(half_lfreq)*nyq
posfreq=abs(freq_sig1);
figure
plot(freq,posfreq(1:half_lfreq));
[b_low,a_low]=butter(8,0.2);
low=filter(b_low,a_low,quake_data(:,3));
[b_high,a_high]=butter(8,0.8,'high')
[b_band.a_band]=butter(8,[0.2 0.4])
freqz(b_low,a_low)
这是我的代码,quake_data里面一共有三个信号波,但是用上面代码滤波后出图结果都一样,麻烦请看看代码应该如何修改.十分感谢了~
请问,滤波后如何出图呢?是否用需用反傅里叶变化?freq_sig1=fft(quake_data(:,4)); lfreq=length(freq_sig1); nyq=50; half_lfreq=floor(lfreq/2); freq=[1:1:(half_lfreq)]/(half_lfreq)*nyq posfreq=abs(freq_sig1); figureplot(freq,posfreq(1:h
如果我没记错,freqz函数是会画图的.所以你最后得到的图就是freqz(b_low,a_low).