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3D Matrix Multiplication

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Hi I have created two large matrices of which I have reshaped to create the following:
A = 3x1x4 double
B = 3x3x4 double
C = B * A ????
I was wondering how I could multiply each 3x3 matrix from B with each 3x1 matrix from A? The aim is to create a new 3x1x4 matrix in the end. Note: I don't have R2020b so don't have access to the pagemtimes function.
Any help is greatly appreciated, thanks!

Accepted Answer

the cyclist
the cyclist on 24 Feb 2021
Edited: the cyclist on 24 Feb 2021
You can do it straightforwardly with a for loop:
% Some made-up input data
A = rand(3,1,4);
B = rand(3,3,4);
[mA,nA,pA] = size(A);
[mB,nB,pB] = size(B);
C = zeros(mB,nA,pA);
for np = 1:pA
C(:,:,np) = B(:,:,np) * A(:,:,np);
  1 Comment
Rahul Marwaha
Rahul Marwaha on 25 Feb 2021
Thanks, that worked perfectly!

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