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vpde_lecture34 [2020/04/21 08:42]
trinh 		vpde_lecture34 [2020/04/23 08:16] (current)
trinh
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 ====== Lecture 34: The maths of music I ====== ====== Lecture 34: The maths of music I ======
 +
 +<html>
 +<iframe width="560" height="315" src="https://www.youtube.com/embed/iedsP762EmE" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 +</html>
  
 ===== The Fourier spectra ===== ===== The Fourier spectra =====
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 <Code:Matlab linenums:1 | Make a sound> <Code:Matlab linenums:1 | Make a sound>
-N = length(f2); +N = length(f); 
-yhat = fft(f2);+yhat = fft(f);
 A = abs(yhat)/N; A = abs(yhat)/N;
 K = (Fs/2)*(1:ceil(N/2))/ceil(N/2); K = (Fs/2)*(1:ceil(N/2))/ceil(N/2);
 A = A(1:ceil(N/2)); A = A(1:ceil(N/2));
 +plot(K, A)
 </Code> </Code>
 +
 +(We noticed during the lecture that the above code is flawed by 1 element, as it indicates a peak frequency of 441Hz instead of 440Hz! I believe this is because you have to 'dump' one of the vector components).
Last modified: 2020/04/21 08:42