Function has_mutual 

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

Check whether a directed graph has any mutual (reciprocal) edges.

For undirected graphs, returns true if there is at least one edge (all edges are mutual by definition).

Self-loops are considered mutual if loops is true.

Examples

use rust_igraph::{Graph, has_mutual};

let mut g = Graph::new(3, true).unwrap();
g.add_edge(0, 1).unwrap();
g.add_edge(1, 2).unwrap();
assert!(!has_mutual(&g, false).unwrap());

g.add_edge(1, 0).unwrap();
assert!(has_mutual(&g, false).unwrap());