I need to find the standard inverse of a large n*n matrix N (n=1,000,000).
I know that N*R=B and I have the matrix B, of the shape (n,k) (k=1,000).
I have the Moore-Penrose Inverse of matrix R (n,k).
I multiplied the B and the inverted R, and got a (n,n) matrix M. The sum of each row in M is very close to what the sum of each row in the standard inverse of N should be, but the actual values in M are not what I expect to have in N.
Please help me find the standard inverse of N.