Output matrix dimension mismatch in for loop

Hi guys, I am having problem with storing the peaks of my data in a for loop. It said subscripted assignment dimension mismatch. I am guessing may be the number of peaks is not the same for all the values in the loop. Here is a simplified version of my codes:

q = 0;
g= 0;

for A = 0:pi/2:4*pi;
 for  B = 1:1:10;
     y(q+1) = sin(A*B);
     H(q+1) = B;
     q = q+1;
 end
 q = 0;

   C(g+1,:) = y;
   [pks,locs] = findpeaks(C(g+1,:));
   D(g+1,:) = pks;
   E(g+1,:) = B(locs);

   g = g+1;
  end

plot(H,y)
g = 0;

How can I store my peaks and the corresponding x values?

Thanks guys!

Answer 1

[Jan]

Please post the complete error message, such that we do not have to guess the line, which causes the problem. I guess boldly:

C(g+1,:) = y;

Here y is a [1, q+1] row vector. Assigning it to a row of C requires, the C has the same number of columns. But this cannot be true over multiple iterations.

You did not include comments in the code. Without a description of what you want to achieve, suggestion a solution is an educated guess only.

[EDITED] The number of peaks differ between the iterations (I guess), then store them in a cell array:

Av = 0:pi/2:4*pi;
D = cell(1, numel(Av));
for A = Av
  ...
  [pks,locs] = findpeaks(C(g+1,:));
  D{g+1} = pks;
  ...

[Catherine]

Hi Jan, thanks for your reply. Here is the full error message:

Subscripted assignment dimension mismatch.
Error in Untitled (line 18)
D(g+1,:) = pks;

What I want to do is to get all the peaks for all the iterations.

[Jan]

See [EDITED] in my answer.

[Catherine]

Hi Jan, thanks so much for that. That worked perfectly! Just one last thing, is it possible to convert the cell array back to matrix with each entry occupying a new row? I have tried cell2mat but that just change it to a row vector with all the results which I can't identify which results belong to which iteration.The following is my results:

[]  [1,1]  [3.67394039744206e-16,6.12323399573677e-16,8.57252759403147e-16,1.10218211923262e-15]  [1,1]  []  [1,1]  [1.10218211923262e-15,5.38968387752153e-15,-9.80955400591059e-16,6.85926003649836e-15]  [1,1]  []

I know the different length of the results will be a problem. Can it fill the empty cell with zeros to make up the same length? Something like the following matrix:

0 0 0 0
1 1 0 0
3.67394039744206e-16  6.12323399573677e-16  8.57252759403147e-16  1.10218211923262e-15
1 1 0 0
0 0 0 0
....... so on