Function complementer 

pub fn complementer(graph: &Graph, loops: bool) -> IgraphResult<Graph>

Returns the complementer of graph.

If loops == true, self-loops (v, v) are added for every vertex that does not already have one. If loops == false, no self-loops appear in the output regardless of the input.

The output’s vertex count equals the input’s; the output’s edge count is n*(n-1) − ecount (directed) or n*(n-1)/2 − ecount (undirected) when loops == false, plus n extra slots if loops == true for self-loops not in the input.

Examples

use rust_igraph::{Graph, complementer};

// Path 0-1-2 → complementer is the single edge (0, 2).
let mut g = Graph::with_vertices(3);
g.add_edge(0, 1).unwrap();
g.add_edge(1, 2).unwrap();
let c = complementer(&g, false).unwrap();
assert_eq!(c.ecount(), 1);
assert_eq!(c.edge(0).unwrap(), (0, 2));