Function diameter_ratio 

pub fn diameter_ratio(graph: &Graph) -> IgraphResult<f64>

Compute the diameter ratio.

diameter / (n - 1) — the diameter normalized by the maximum possible diameter (a path graph). Values near 1 indicate the graph is elongated; values near 0 indicate short diameters (e.g. complete graphs). Returns 0.0 for disconnected or trivial graphs.

Examples

use rust_igraph::{Graph, diameter_ratio};

// Path 0-1-2-3: diameter=3, n=4 → 3/3 = 1.0
let g = Graph::from_edges(&[(0,1),(1,2),(2,3)], false, Some(4)).unwrap();
assert!((diameter_ratio(&g).unwrap() - 1.0).abs() < 1e-10);