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matrix - How do I put matrices next to each other?



So I want to be able to put matrices "next to each other", or in other words if I have two matrices A that is n×k and B that is n×m, I want to be able to create a matrix C that is n×(k+m) so that the (k+1)th column of C is the first column of B.


This should be really easy, and in matlab it is (C= [A B]), but I can't figure it out in mathematica




Answer



Like this?


(a = ConstantArray["A", {4, 3}]) // MatrixForm

enter image description here


(b = ConstantArray["B", {4, 4}]) // MatrixForm

enter image description here


Map[Flatten, Transpose[{a, b}]] // MatrixForm


enter image description here


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