I have another matrix operations which seems a little more complicated.
Let A be an n x n matrix and let S be a subset of {0,...,n-1}. Assume
S is represented by a binary vector s, with a 1 at the index i if i is
in S. (e.g. if S={0,3} then s = [1,0,0,1])
I would like to have an efficient way to
I would like to do with numpy the following operation.
Let A be an n x n matrix and let s be an integer between 1 and n.
I would like to have an n x n matrix B = f(A,s) such that
- If we only look at the first s columns of B, we will not see any
difference with respect to the first s columns of
