# What is the format of saving sparse matrix in MATLAB?

We know that for lagre sparse matrices, we can use compressed sparse row (CSR) or compressed sparse column (CSC) format to store the sparse matrices so that we can save CPU memory. And the coordinate format (COO) does not save memory.

My question is that in MATLAB, a sparse matrix $$A$$ can be indexed for example, A(1,2), so is COO format for sparse matrix used in MATLAB? Because COO is not cheap, MATLAB instead is an optimal software, I think matlab must have considered this issue. How is MATLAB store the sparse matrix? Thanks very much.