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Clutch
Posts:
8
Registered:
2/19/12


How to copy a submatrix/vector along diagonal of a larger matrix ?
Posted:
Mar 8, 2013 8:16 AM


I want to create a matrix below where I copy A = [1 2 3] allow the diagonal of a matrix.
[ 1 2 3 0 0 0 0 0 0 0 0 0
0 0 1 2 3 0 0 0 0 0 0 0
0 0 0 0 0 0 1 2 3 0 0 0
0 0 0 0 0 0 0 0 0 1 2 3]
I know I can use blkdiag(A ,A, A, A) which will do the job however the number of parameters vary in my code. Sometimes, there may be five A vectors or 20 A vectors that I need to create such a matrix. Let's say this is a variable that the user inputs
How can I do this efficiently in code?



