Struct const_graphs::Graph

pub struct Graph<const SIZE: usize> { /* private fields */ }

Compile time graphs.

use const_graphs::Graph;

const SIZE: usize = 1_000;
// You can use const.
const graph1: Graph<SIZE> = Graph::new();
 
// And, static.
static mut graph2: Graph<SIZE> = Graph::new();
unsafe {
  graph2.add_edge(0, 1);
  assert!(graph2.has_edge(0, 1));
}

// And, of course, let too:
let graph3 = Graph::<SIZE>::new();

Implementations

impl<const SIZE: usize> Graph<SIZE>

pub const fn add_edge(&mut self, i: usize, j: usize)

Add an edge to the graph between i and j.

use const_graphs::Graph;

let mut graph = Graph::<10>::new();
graph.add_edge(0, 1);
assert!(graph.has_edge(0, 1));

See also Graph::add_edge_undirected.

pub const fn add_edge_undirected(&mut self, i: usize, j: usize)

Add an undirected edge to the graph between i and j.

use const_graphs::Graph;

let mut graph = Graph::<10>::new();
graph.add_edge_undirected(0, 1);
assert!(graph.has_edge(0, 1));
assert!(graph.has_edge(1, 0));

See also Graph::add_edge.

pub const fn remove_edge(&mut self, i: usize, j: usize)

Remove an edge from the graph between i and j.

use const_graphs::Graph;

let mut graph = Graph::<10>::new();
graph.add_edge(0, 1);
graph.remove_edge(0, 1);
assert!(!graph.has_edge(0, 1));

See also Graph::remove_edge_undirected.

pub const fn remove_edge_undirected(&mut self, i: usize, j: usize)

Remove an undirected edge from the graph between i and j.

use const_graphs::Graph;

let mut graph = Graph::<10>::new();
graph.add_edge_undirected(0, 1);
graph.remove_edge_undirected(0, 1);
assert!(!graph.has_edge(0, 1));
assert!(!graph.has_edge(1, 0));

See also Graph::remove_edge.

pub const fn has_edge(&self, i: usize, j: usize) -> bool

Checks whether there is an edge between i and j.

use const_graphs::Graph;

let mut graph = Graph::<10>::new();
// The graph is initialized empty.
assert!(!graph.has_edge(0, 1));

pub const fn get_edges(&self, vertex: usize) -> &[bool; SIZE]

Returns an array where the ith element is a boolean representing whether there is an edge between vertex and i.

use const_graphs::Graph;

let mut graph = Graph::<3>::new();
graph.add_edge(0, 2);
assert_eq!(graph.get_edges(0), &[false, false, true]);

See also Graph::get_inverse_edges.

pub const fn get_inverse_edges(&self, vertex: usize) -> [bool; SIZE]

Returns an array where the ith element is a boolean representing whether there is an edge between i and vertex. This is useful in a few graph algorithms where you need to know which vertices “point” to the current, and not the contrary.

use const_graphs::Graph;

let mut graph = Graph::<3>::new();
graph.add_edge(0, 2);
assert_eq!(
  graph.get_inverse_edges(2),
  [true, false, false]
);

See also Graph::get_edges.

pub const fn max_number_of_edges(&self) -> usize

Returns the maximum number of edges of a graph.

use const_graphs::Graph;

let graph = Graph::<3>::new();
// The possible edges are:
// 0 -> 1
// 0 -> 2
// 1 -> 0
// 1 -> 2
// 2 -> 0
// 2 -> 1
assert_eq!(graph.max_number_of_edges(), 6);

pub const fn density(&self) -> f32

Returns the density of a graph, that is, the ratio between the number of edges and the maximum number of possible edges.

use const_graphs::Graph;

let mut graph = Graph::<3>::new();
graph.add_edge_undirected(0, 1);
graph.add_edge_undirected(0, 2);
graph.add_edge_undirected(1, 2);
assert_eq!(graph.density(), 1.0);

pub const fn clear(&mut self)

Remove all edges from the graph.

use const_graphs::Graph;

let mut graph = Graph::<3>::new();
graph.add_edge_undirected(0, 1);
graph.add_edge_undirected(0, 2);
graph.add_edge_undirected(1, 2);
graph.clear();

assert_eq!(graph.density(), 0.0);

pub const fn new() -> Graph<SIZE>

Creates a new graph.

use const_graphs::Graph;

const SIZE: usize = 10;
let graph = Graph::<SIZE>::new();