MATLAB: How to full fill the diagonal of a matrix by a vector

circshiftdiagonal matrix

hello
how can i full fill a matrix (17*9) by a vector by length 9
for example i have the vector d=[1 2 3 ] and the matrix zeros(5*5) and i want to make the output matrix like this
1 0 0 3 2
2 1 0 0 3
3 2 1 0 0
0 3 2 1 0
0 0 3 2 1
thanks

Best Answer

This approach uses circshift() to circularly shift the columns of matrix. 
m = zeros(5,5); 
v = [1,2,3]; 
% Loop through each column of m
for i = 1:size(m,2)
    m(1:length(v),i) = v; 
    m(:,i) = circshift(m(:,1), i-1);
end
Result:
m =
     1     0     0     3     2
     2     1     0     0     3
     3     2     1     0     0
     0     3     2     1     0
     0     0     3     2     1
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