I have a big matrix B and I get it by concatenating the small matrices.
B = [A1 M1 M2 Z1
M1' M2' Z2 A2];
But when I store this matrix, its size is very big and it takes up a lot of memory. I want to convert it to sparse matrix. The matrices Z1 and Z2 have all zero elements and, M1 and M2 also have a lot of zeros.