Function hrg_fit 

pub fn hrg_fit(
    graph: &Graph,
    start_hrg: Option<&HrgTree>,
    steps: u64,
    seed: u64,
) -> IgraphResult<HrgTree>

Fit a hierarchical random graph model to a network using MCMC.

If start_hrg is provided, the MCMC begins from that dendrogram structure; otherwise a random initial tree is used.

steps controls the MCMC budget:

• If steps > 0, exactly that many MCMC moves are performed.
• If steps == 0, the chain runs until convergence (mean log-likelihood stabilizes over 65536-step windows).

Errors

Returns an error if the graph has fewer than 3 vertices.

Example

use rust_igraph::{Graph, hrg_fit};

let g = Graph::from_edges(
    &[(0,1),(1,2),(2,3),(3,4),(4,0),(0,2),(1,3)],
    false, Some(5)
).unwrap();
let hrg = hrg_fit(&g, None, 1000, 42).unwrap();
assert_eq!(hrg.size(), 5);