DIVIDING and MUlLTIPLYING multidimensional matrices

Hello, I am quite a new to Matlab. I am struggling to find a way how to DIVIDE and MULTIPLICATE multidimensional complex matrices. Suppose that matrices are A (2x2) and B(2x2) both with 100 arrays.Thank you a lot..

[Stephen23]

"Suppose that matrices are A[2,2,:] and B[2,2,:]."

That is not MATLAB syntax, so it is not clear what you mean. What sizes are the arrays that you wish to multiply and/or divide?

[Jan]

I agree with Stephen: How does "A[2,2,:]" define a matrix? "Matrices" have 2 dimensions by definition, but I can guess, that you mean "multidimensional arrays". Then it matters if you can to multiply the arrays elementwise or if a matrix multiplication is wanted. Please edit the question and add these information.

[Peter Jakbisin]

I am sorry for not being exact in specification of matrix.. we talk about matrices (A and B)contains 2 rows and 2 columns (2x2) and both have 100 arrays. I don't want to make elementwise multiplication, however.

[James Tursa]

Please post the following:

class(A)
class(B)
size(A)
size(B)

[Jan]

2x2 matrices have 4 elements, but they cannot "have 100 arrays". Matrices do not have arrays at all, but they are a special arrays, namely with 2 dimensions.

Now we know, that you do not want an elementwise multiplication, but what to you want instead?

[Stephen23]

"we talk about matrices (A and B)contains 2 rows and 2 columns (2x2) and both have 100 arrays"

Are A and B cell arrays or structure arrays, containing numeric matrices?

Answer 1

[Jan]

Because I do not understand, what your inputs are, it is a bold guess only to suggest these functions:

• https://www.mathworks.com/matlabcentral/fileexchange/47092-vectorized-multi-dimensional-matrix-multiplication
• https://www.mathworks.com/matlabcentral/fileexchange/10062-multi-dimensional-matrix-product--outer-product-and-partial-trace
• https://www.mathworks.com/matlabcentral/fileexchange/16275-tprod-arbitary-tensor-products-between-n-d-arrays
• https://www.mathworks.com/matlabcentral/fileexchange/25977-mtimesx-fast-matrix-multiply-with-multi-dimensional-support
• https://www.mathworks.com/matlabcentral/fileexchange/37515-mmx-multithreaded-matrix-operations-on-n-d-matrices