pub unsafe extern "C" fn igraph_layout_gem(
graph: *const igraph_t,
res: *mut igraph_matrix_t,
use_seed: igraph_bool_t,
maxiter: igraph_int_t,
temp_max: igraph_real_t,
temp_min: igraph_real_t,
temp_init: igraph_real_t,
) -> igraph_error_t