fixed_r = OK fixed_c = OK pt_r(fixed_r) = OK pt_c(fixed_c) = OK pt_r(fixed_c) = OK pt_c(fixed_r) = OK dense_r = OK dense_c = OK pt_r(dense_r) = OK pt_c(dense_c) = OK pt_r(dense_c) = OK pt_c(dense_r) = OK sparse_r = OK sparse_c = OK pt_r(sparse_r) = OK pt_c(sparse_c) = OK pt_r(sparse_c) = OK pt_c(sparse_r) = OK