What is the shortest way to make matrix from a vector using the 1-of-K coding scheme?

How to make matrix from a vector using the 1-of-K coding scheme but without a for cycle? (1,1,2,3,1,3,2) to (1,0,0; 1,0,0; 0,1,0; 0,0,1; 1,0,0; 0,0,1; 0,1,0)

Answer 1

[Stephen23]

This is easy using sub2ind:

>> C = [1,1,2,3,1,3,2];
>> R = 1:numel(C);
>> A = zeros(numel(C),max(C));
>> A(sub2ind(size(A),R,C)) = 1
A =
     1     0     0
     1     0     0
     0     1     0
     0     0     1
     1     0     0
     0     0     1
     0     1     0