Function igraph_sparse_weighted_adjacency 

pub unsafe extern "C" fn igraph_sparse_weighted_adjacency(
    graph: *mut igraph_t,
    adjmatrix: *mut igraph_sparsemat_t,
    mode: igraph_adjacency_t,
    weights: *mut igraph_vector_t,
    loops: igraph_loops_t,
) -> igraph_error_t