Function residual_graph 

pub fn residual_graph(
    graph: &Graph,
    capacity: &[f64],
    flow: &[f64],
) -> IgraphResult<ResidualGraphResult>

Compute the residual graph given capacity and flow vectors.

For each edge e where capacity[e] - flow[e] > 0, the residual graph contains the same edge with residual capacity capacity[e] - flow[e].

Errors

Returns an error if capacity or flow length differs from the edge count.

Examples

use rust_igraph::{Graph, residual_graph};

let mut g = Graph::new(3, true).unwrap();
g.add_edge(0, 1).unwrap(); // edge 0
g.add_edge(1, 2).unwrap(); // edge 1
let capacity = vec![10.0, 5.0];
let flow = vec![7.0, 5.0];
let result = residual_graph(&g, &capacity, &flow).unwrap();
// Edge 0 has residual 3.0, edge 1 is saturated (removed)
assert_eq!(result.graph.vcount(), 3);
assert_eq!(result.graph.ecount(), 1);
assert_eq!(result.capacity, vec![3.0]);