MATLAB: Help to multiply matrices in succession

for loopindexingMATLABmatrix

Hi,
I initialized this objects:
C = vpa(zeros(4, 4, N));
A = vpa(zeros(4,4,N));
where C is:
for i = 1:N
      C(:,:,i) = [(cos(theta(i))) (-sin(theta(i))).*(cos(alpha(i))) (sin(theta(i))).*(sin(alpha(i))) (a(i)).*(cos(theta(i)));
      (sin(theta(i))) (cos(theta(i))).*(cos(alpha(i))) (-cos(theta(i))).*(sin(alpha(i))) (a(i)).*(sin(theta(i)));
      0 sin(alpha(i)) cos(alpha(i)) d(i);
      0 0 0 1];
  end
Well, I need that
A(:,:,1)=C(:,:,1);
but elements:
A(:,:,2) ……. A(:,:,N) must be obtained as
A(:,:,2) = C(:,:,1) * C(:,:,2)
A(:,:,3) = C(:,:,1) * C(:,:,2) * C(:,:,3)
etc
....
A(:,:,N) = C(:,:,1) * C(:,:,2) * C(:,:,3) * ....* C(:,:,N)
some tips ?

Best Answer

% For example:
C = randi(10,2,2,3)
A = cumprod(C,3)
Or perhaps you meant:
A(:,:,1) = C(:,:,1);
for ii = 2:size(C,3)
   A(:,:,ii) = A(:,:,ii-1)*C(:,:,ii);
end
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