Plot discrete fourier transform of a sine wave

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Hi, I want to plot the sampled signal in frequency domain which means I need to use the discrete fourier transform, right? But when I run the code below I only get the display of sampled signal in discrete time domain and an error saying vector lengths must match came out on the command window. What does this mean? And what should be fixed? Please help me.
%chap1-38a
f = 6000;
fs = 16000;
w = 2*pi*(f/fs);
n = 0:50;
y = sin(w.*n);
subplot(2,1,1);
stem(n,y);
f = -fs/2:fs/(N-1):fs/2;
z = fftshift(fft(x));
subplot(2,1,2);
plot(f,abs(z));
The display when I run the code.

Accepted Answer

Star Strider
Star Strider on 10 May 2021
Try this —
f = 6000;
fs = 16000;
w = 2*pi*(f/fs);
N = 50;
n = 0:N;
y = sin(w.*n);
subplot(2,1,1);
stem(n,y);
f = -fs/2:fs/(N):fs/2;
z = fftshift(fft(y));
subplot(2,1,2);
plot(f,abs(z));
I will let you discover the changes I made that are necessary to make it run!
  2 Comments
Cynthia Lucy
Cynthia Lucy on 10 May 2021
Ive found the changes you made and now I understand what is wrong with my previous code! Thank you so much for your help! @Star Strider

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