Function eccentric_distance_sum 

pub fn eccentric_distance_sum(graph: &Graph) -> IgraphResult<u64>

Compute the eccentric-distance sum.

ξ^d(G) = Σ_{v∈V} ε(v) · D(v)

where D(v) = Σ_{u} dist(v,u) is the distance sum of v. Returns 0 for empty graphs. Disconnected components contribute only within their own component.

Examples

use rust_igraph::{Graph, eccentric_distance_sum};

// Path 0-1-2: ecc [2,1,2], D [3,2,3]
// ξ^d = 2·3 + 1·2 + 2·3 = 14
let g = Graph::from_edges(&[(0,1),(1,2)], false, Some(3)).unwrap();
assert_eq!(eccentric_distance_sum(&g).unwrap(), 14);