Subplot for for loop

I just want to make a simple sub plot but i cannot get around the range and domain parameters. many thanks in advance

Ts=1/128;
Fs=1/Ts;
for N=[32 64 128 256 512 1024]
    n=0:N-1;
    x=sin(20*pi*n*Ts)+sin(11*pi*n*Ts)+cos(121*pi*n*Ts/2);

      freqresol=Fs/N;
      freq=(-Fs/2):freqresol:(Fs/2-freqresol);
      XF=fftshift(fft(x));
      figure
      plot(freq,abs(XF)/N);
      xlim([-20*pi 20*pi])
      title(['N = ',num2str(N)])
      suptitle('x=sin(20*pi*n*Ts)+sin(11*pi*n*Ts)+cos(121*pi*n*Ts/2)')
  end

[Rik]

You are creating a new figure each loop iteration. Also, you are not using the subplot function to create smaler axes objects, so using suptitle is not necessary (nor is having it inside your loop).

Answer 1

[M]

The help of https://mathworks.com/help/matlab/ref/subplot.html says:

subplot(m,n,p) divides the current figure into an m-by-n grid and creates axes in the position specified by p.

So in your case you can use something like:

idx=1;
for N=[...]
   ...
   subplot(3,2,idx)
   plot(freq,abs(XF)/N);
   xlim([-20*pi 20*pi])
   title(['N = ',num2str(N)])
   idx=idx+1;
end