How can I plot FFT (Fast Fourier Transform) in a for loop?

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Jose Peñaloza 2015-8-13

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https://ww2.mathworks.cn/matlabcentral/answers/233769-how-can-i-plot-fft-fast-fourier-transform-in-a-for-loop

编辑： Jose Peñaloza 2015-8-13

I have this code, it works until m=numfiles, the last part is a code I used for FFT only for one file but I want to adapt in a for-end loop. Data is in cells. I tried to adapt but it doesn't work.

files= dir('*.avi');
  numfiles=length(files);
  mydata= cell(numfiles,1);
  info=cell(numfiles,1);
  isFileSupported =  true(numfiles, 1) ;
  for j=1:numfiles
    try
        info{j}=mmfileinfo(files(j).name);
        audio = info{j}.Audio
        video = info{j}.Video
    catch ME
        isFileSupported(j) = false;
        continue;
    end
  end
     supportedFiles = files(isFileSupported);
     for k=1:numel(supportedFiles)
         mydata{k}=importdata(supportedFiles(k).name);
     end
      if true
        % code
      end
     m=numfiles
      nfft=2^nextpow2(m);  
      Numnfft=length(nfft);
      x_HannWind=x.*hanning(m); 
      Y=fft(x_HandWind,nfft)/m; %Fast Fourier Transform%
      length(Y);
      Y_mag = abs(Y); %Magnitude  FFT%
      plot(Y_mag);
      xlabel('Frecuence [Hz]')
      ylabel('Magnitude')
      end