# Matrix multiplication along a specified dimension?

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Darcy Cordell on 28 Sep 2022
Commented: James Tursa on 28 Sep 2022
I have a 2x2xN matrix, A, and a 2xN matrix, X. I want to multiply each Nth 2x2 matrix in A by the Nth 2x1 matrix in X. I can do this with:
for i = 1:N
B(:,i) = A(:,:,i)*X(:,i);
end
However, this is very slow, especially in my case where N is large.
Is there a way to do matrix multiplication "along a specified dimension" without a for loop?
Apologies if this is a duplicate question, I looked and could not find anything. Most of the other answers I found involve element-wise multiplication along a specified dimension, which is different than what I am doing.

Matt J on 28 Sep 2022
B=pagemtimes(A,X)
##### 2 CommentsShowHide 1 older comment
James Tursa on 28 Sep 2022
Or reshape(X,2,1,[]);

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