Function igraph_get_laplacian 

pub unsafe extern "C" fn igraph_get_laplacian(
    graph: *const igraph_t,
    res: *mut igraph_matrix_t,
    mode: igraph_neimode_t,
    normalization: igraph_laplacian_normalization_t,
    weights: *const igraph_vector_t,
) -> igraph_error_t