matlab - Matrix to Diagonal Matrix -

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• how vectorize row-wise diagonalization of matrix 3 answers

let's have matrix in matlab like

a = [1 2 3;       4 5 6;       7 8 9] 

and obtain matrix of form

b = [1 0 0;        0 4 0;       0 0 7;      2 0 0;      0 5 0;      0 0 8;      3 0 0;      0 6 0;      0 0 9] 

i.e. matrix concatenation of 3 diagonal matrices, each having columns of matrix @ diagonals. know how using loop on columns of , concatenating results looking shorter way this. please share ideas.

b(repmat(eye(3),3,1)==1) = a; reshape(b, [], 3)