| //! `GraphMap<N, E, Ty>` is a graph datastructure where node values are mapping |
| //! keys. |
| |
| use indexmap::map::Keys; |
| use indexmap::map::{Iter as IndexMapIter, IterMut as IndexMapIterMut}; |
| use indexmap::IndexMap; |
| use std::cmp::Ordering; |
| use std::collections::HashSet; |
| use std::fmt; |
| use std::hash::{self, Hash}; |
| use std::iter::FromIterator; |
| use std::iter::{Cloned, DoubleEndedIterator}; |
| use std::marker::PhantomData; |
| use std::mem; |
| use std::ops::{Deref, Index, IndexMut}; |
| use std::slice::Iter; |
| |
| use crate::{Directed, Direction, EdgeType, Incoming, Outgoing, Undirected}; |
| |
| use crate::graph::node_index; |
| use crate::graph::Graph; |
| use crate::visit; |
| use crate::IntoWeightedEdge; |
| |
| #[cfg(feature = "rayon")] |
| use indexmap::map::rayon::ParKeys; |
| #[cfg(feature = "rayon")] |
| use rayon::{iter::plumbing::UnindexedConsumer, prelude::*}; |
| |
| /// A `GraphMap` with undirected edges. |
| /// |
| /// For example, an edge between *1* and *2* is equivalent to an edge between |
| /// *2* and *1*. |
| pub type UnGraphMap<N, E> = GraphMap<N, E, Undirected>; |
| /// A `GraphMap` with directed edges. |
| /// |
| /// For example, an edge from *1* to *2* is distinct from an edge from *2* to |
| /// *1*. |
| pub type DiGraphMap<N, E> = GraphMap<N, E, Directed>; |
| |
| /// `GraphMap<N, E, Ty>` is a graph datastructure using an associative array |
| /// of its node weights `N`. |
| /// |
| /// It uses an combined adjacency list and sparse adjacency matrix |
| /// representation, using **O(|V| + |E|)** space, and allows testing for edge |
| /// existence in constant time. |
| /// |
| /// `GraphMap` is parameterized over: |
| /// |
| /// - Associated data `N` for nodes and `E` for edges, called *weights*. |
| /// - The node weight `N` must implement `Copy` and will be used as node |
| /// identifier, duplicated into several places in the data structure. |
| /// It must be suitable as a hash table key (implementing `Eq + Hash`). |
| /// The node type must also implement `Ord` so that the implementation can |
| /// order the pair (`a`, `b`) for an edge connecting any two nodes `a` and `b`. |
| /// - `E` can be of arbitrary type. |
| /// - Edge type `Ty` that determines whether the graph edges are directed or |
| /// undirected. |
| /// |
| /// You can use the type aliases `UnGraphMap` and `DiGraphMap` for convenience. |
| /// |
| /// `GraphMap` does not allow parallel edges, but self loops are allowed. |
| /// |
| /// Depends on crate feature `graphmap` (default). |
| #[derive(Clone)] |
| pub struct GraphMap<N, E, Ty> { |
| nodes: IndexMap<N, Vec<(N, CompactDirection)>>, |
| edges: IndexMap<(N, N), E>, |
| ty: PhantomData<Ty>, |
| } |
| |
| impl<N: Eq + Hash + fmt::Debug, E: fmt::Debug, Ty: EdgeType> fmt::Debug for GraphMap<N, E, Ty> { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| self.nodes.fmt(f) |
| } |
| } |
| |
| /// A trait group for `GraphMap`'s node identifier. |
| pub trait NodeTrait: Copy + Ord + Hash {} |
| impl<N> NodeTrait for N where N: Copy + Ord + Hash {} |
| |
| // non-repr(usize) version of Direction |
| #[derive(Copy, Clone, Debug, PartialEq)] |
| enum CompactDirection { |
| Outgoing, |
| Incoming, |
| } |
| |
| impl CompactDirection { |
| /// Return the opposite `CompactDirection`. |
| #[inline] |
| pub fn opposite(self) -> CompactDirection { |
| match self { |
| CompactDirection::Outgoing => CompactDirection::Incoming, |
| CompactDirection::Incoming => CompactDirection::Outgoing, |
| } |
| } |
| } |
| |
| impl From<Direction> for CompactDirection { |
| fn from(d: Direction) -> Self { |
| match d { |
| Outgoing => CompactDirection::Outgoing, |
| Incoming => CompactDirection::Incoming, |
| } |
| } |
| } |
| |
| impl From<CompactDirection> for Direction { |
| fn from(d: CompactDirection) -> Self { |
| match d { |
| CompactDirection::Outgoing => Outgoing, |
| CompactDirection::Incoming => Incoming, |
| } |
| } |
| } |
| |
| impl PartialEq<Direction> for CompactDirection { |
| fn eq(&self, rhs: &Direction) -> bool { |
| (*self as usize) == (*rhs as usize) |
| } |
| } |
| |
| #[cfg(feature = "serde-1")] |
| impl<N, E, Ty> serde::Serialize for GraphMap<N, E, Ty> |
| where |
| Ty: EdgeType, |
| N: NodeTrait + serde::Serialize, |
| E: serde::Serialize, |
| GraphMap<N, E, Ty>: Clone, |
| { |
| /// Serializes the given `GraphMap` into the same format as the standard |
| /// `Graph`. Needs feature `serde-1`. |
| /// |
| /// Note: the graph has to be `Clone` for this to work. |
| fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> |
| where |
| S: serde::Serializer, |
| { |
| let cloned_graph: GraphMap<N, E, Ty> = GraphMap::clone(self); |
| let equivalent_graph: Graph<N, E, Ty, u32> = cloned_graph.into_graph(); |
| equivalent_graph.serialize(serializer) |
| } |
| } |
| |
| #[cfg(feature = "serde-1")] |
| impl<'de, N, E, Ty> serde::Deserialize<'de> for GraphMap<N, E, Ty> |
| where |
| Ty: EdgeType, |
| N: NodeTrait + serde::Deserialize<'de>, |
| E: Clone + serde::Deserialize<'de>, |
| { |
| /// Deserializes into a new `GraphMap` from the same format as the standard |
| /// `Graph`. Needs feature `serde-1`. |
| /// |
| /// **Warning**: When deseralizing a graph that was not originally a `GraphMap`, |
| /// the restrictions from [`from_graph`](#method.from_graph) apply. |
| /// |
| /// Note: The edge weights have to be `Clone` for this to work. |
| fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> |
| where |
| D: serde::Deserializer<'de>, |
| { |
| let equivalent_graph: Graph<N, E, Ty, u32> = Graph::deserialize(deserializer)?; |
| Ok(GraphMap::from_graph(equivalent_graph)) |
| } |
| } |
| |
| impl<N, E, Ty> GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| /// Create a new `GraphMap` |
| pub fn new() -> Self { |
| Self::default() |
| } |
| |
| /// Create a new `GraphMap` with estimated capacity. |
| pub fn with_capacity(nodes: usize, edges: usize) -> Self { |
| GraphMap { |
| nodes: IndexMap::with_capacity(nodes), |
| edges: IndexMap::with_capacity(edges), |
| ty: PhantomData, |
| } |
| } |
| |
| /// Return the current node and edge capacity of the graph. |
| pub fn capacity(&self) -> (usize, usize) { |
| (self.nodes.capacity(), self.edges.capacity()) |
| } |
| |
| /// Use their natural order to map the node pair (a, b) to a canonical edge id. |
| #[inline] |
| fn edge_key(a: N, b: N) -> (N, N) { |
| if Ty::is_directed() || a <= b { |
| (a, b) |
| } else { |
| (b, a) |
| } |
| } |
| |
| /// Whether the graph has directed edges. |
| pub fn is_directed(&self) -> bool { |
| Ty::is_directed() |
| } |
| |
| /// Create a new `GraphMap` from an iterable of edges. |
| /// |
| /// Node values are taken directly from the list. |
| /// Edge weights `E` may either be specified in the list, |
| /// or they are filled with default values. |
| /// |
| /// Nodes are inserted automatically to match the edges. |
| /// |
| /// ``` |
| /// use petgraph::graphmap::UnGraphMap; |
| /// |
| /// // Create a new undirected GraphMap. |
| /// // Use a type hint to have `()` be the edge weight type. |
| /// let gr = UnGraphMap::<_, ()>::from_edges(&[ |
| /// (0, 1), (0, 2), (0, 3), |
| /// (1, 2), (1, 3), |
| /// (2, 3), |
| /// ]); |
| /// ``` |
| pub fn from_edges<I>(iterable: I) -> Self |
| where |
| I: IntoIterator, |
| I::Item: IntoWeightedEdge<E, NodeId = N>, |
| { |
| Self::from_iter(iterable) |
| } |
| |
| /// Return the number of nodes in the graph. |
| pub fn node_count(&self) -> usize { |
| self.nodes.len() |
| } |
| |
| /// Return the number of edges in the graph. |
| pub fn edge_count(&self) -> usize { |
| self.edges.len() |
| } |
| |
| /// Remove all nodes and edges |
| pub fn clear(&mut self) { |
| self.nodes.clear(); |
| self.edges.clear(); |
| } |
| |
| /// Add node `n` to the graph. |
| pub fn add_node(&mut self, n: N) -> N { |
| self.nodes.entry(n).or_insert(Vec::new()); |
| n |
| } |
| |
| /// Return `true` if node `n` was removed. |
| /// |
| /// Computes in **O(V)** time, due to the removal of edges with other nodes. |
| pub fn remove_node(&mut self, n: N) -> bool { |
| let links = match self.nodes.swap_remove(&n) { |
| None => return false, |
| Some(sus) => sus, |
| }; |
| for (succ, dir) in links { |
| let edge = if dir == CompactDirection::Outgoing { |
| Self::edge_key(n, succ) |
| } else { |
| Self::edge_key(succ, n) |
| }; |
| // remove all successor links |
| self.remove_single_edge(&succ, &n, dir.opposite()); |
| // Remove all edge values |
| self.edges.swap_remove(&edge); |
| } |
| true |
| } |
| |
| /// Return `true` if the node is contained in the graph. |
| pub fn contains_node(&self, n: N) -> bool { |
| self.nodes.contains_key(&n) |
| } |
| |
| /// Add an edge connecting `a` and `b` to the graph, with associated |
| /// data `weight`. For a directed graph, the edge is directed from `a` |
| /// to `b`. |
| /// |
| /// Inserts nodes `a` and/or `b` if they aren't already part of the graph. |
| /// |
| /// Return `None` if the edge did not previously exist, otherwise, |
| /// the associated data is updated and the old value is returned |
| /// as `Some(old_weight)`. |
| /// |
| /// ``` |
| /// // Create a GraphMap with directed edges, and add one edge to it |
| /// use petgraph::graphmap::DiGraphMap; |
| /// |
| /// let mut g = DiGraphMap::new(); |
| /// g.add_edge("x", "y", -1); |
| /// assert_eq!(g.node_count(), 2); |
| /// assert_eq!(g.edge_count(), 1); |
| /// assert!(g.contains_edge("x", "y")); |
| /// assert!(!g.contains_edge("y", "x")); |
| /// ``` |
| pub fn add_edge(&mut self, a: N, b: N, weight: E) -> Option<E> { |
| if let old @ Some(_) = self.edges.insert(Self::edge_key(a, b), weight) { |
| old |
| } else { |
| // insert in the adjacency list if it's a new edge |
| self.nodes |
| .entry(a) |
| .or_insert_with(|| Vec::with_capacity(1)) |
| .push((b, CompactDirection::Outgoing)); |
| if a != b { |
| // self loops don't have the Incoming entry |
| self.nodes |
| .entry(b) |
| .or_insert_with(|| Vec::with_capacity(1)) |
| .push((a, CompactDirection::Incoming)); |
| } |
| None |
| } |
| } |
| |
| /// Remove edge relation from a to b |
| /// |
| /// Return `true` if it did exist. |
| fn remove_single_edge(&mut self, a: &N, b: &N, dir: CompactDirection) -> bool { |
| match self.nodes.get_mut(a) { |
| None => false, |
| Some(sus) => { |
| if Ty::is_directed() { |
| match sus.iter().position(|elt| elt == &(*b, dir)) { |
| Some(index) => { |
| sus.swap_remove(index); |
| true |
| } |
| None => false, |
| } |
| } else { |
| match sus.iter().position(|elt| &elt.0 == b) { |
| Some(index) => { |
| sus.swap_remove(index); |
| true |
| } |
| None => false, |
| } |
| } |
| } |
| } |
| } |
| |
| /// Remove edge from `a` to `b` from the graph and return the edge weight. |
| /// |
| /// Return `None` if the edge didn't exist. |
| /// |
| /// ``` |
| /// // Create a GraphMap with undirected edges, and add and remove an edge. |
| /// use petgraph::graphmap::UnGraphMap; |
| /// |
| /// let mut g = UnGraphMap::new(); |
| /// g.add_edge("x", "y", -1); |
| /// |
| /// let edge_data = g.remove_edge("y", "x"); |
| /// assert_eq!(edge_data, Some(-1)); |
| /// assert_eq!(g.edge_count(), 0); |
| /// ``` |
| pub fn remove_edge(&mut self, a: N, b: N) -> Option<E> { |
| let exist1 = self.remove_single_edge(&a, &b, CompactDirection::Outgoing); |
| let exist2 = if a != b { |
| self.remove_single_edge(&b, &a, CompactDirection::Incoming) |
| } else { |
| exist1 |
| }; |
| let weight = self.edges.remove(&Self::edge_key(a, b)); |
| debug_assert!(exist1 == exist2 && exist1 == weight.is_some()); |
| weight |
| } |
| |
| /// Return `true` if the edge connecting `a` with `b` is contained in the graph. |
| pub fn contains_edge(&self, a: N, b: N) -> bool { |
| self.edges.contains_key(&Self::edge_key(a, b)) |
| } |
| |
| /// Return an iterator over the nodes of the graph. |
| /// |
| /// Iterator element type is `N`. |
| pub fn nodes(&self) -> Nodes<N> { |
| Nodes { |
| iter: self.nodes.keys().cloned(), |
| } |
| } |
| |
| #[cfg(feature = "rayon")] |
| pub fn par_nodes(&self) -> ParNodes<'_, N> |
| where |
| N: Send + Sync, |
| { |
| ParNodes { |
| iter: self.nodes.par_keys(), |
| } |
| } |
| |
| /// Return an iterator of all nodes with an edge starting from `a`. |
| /// |
| /// - `Directed`: Outgoing edges from `a`. |
| /// - `Undirected`: All edges from or to `a`. |
| /// |
| /// Produces an empty iterator if the node doesn't exist.<br> |
| /// Iterator element type is `N`. |
| pub fn neighbors(&self, a: N) -> Neighbors<N, Ty> { |
| Neighbors { |
| iter: match self.nodes.get(&a) { |
| Some(neigh) => neigh.iter(), |
| None => [].iter(), |
| }, |
| ty: self.ty, |
| } |
| } |
| |
| /// Return an iterator of all neighbors that have an edge between them and |
| /// `a`, in the specified direction. |
| /// If the graph's edges are undirected, this is equivalent to *.neighbors(a)*. |
| /// |
| /// - `Directed`, `Outgoing`: All edges from `a`. |
| /// - `Directed`, `Incoming`: All edges to `a`. |
| /// - `Undirected`: All edges from or to `a`. |
| /// |
| /// Produces an empty iterator if the node doesn't exist.<br> |
| /// Iterator element type is `N`. |
| pub fn neighbors_directed(&self, a: N, dir: Direction) -> NeighborsDirected<N, Ty> { |
| NeighborsDirected { |
| iter: match self.nodes.get(&a) { |
| Some(neigh) => neigh.iter(), |
| None => [].iter(), |
| }, |
| start_node: a, |
| dir, |
| ty: self.ty, |
| } |
| } |
| |
| /// Return an iterator of target nodes with an edge starting from `a`, |
| /// paired with their respective edge weights. |
| /// |
| /// - `Directed`: Outgoing edges from `a`. |
| /// - `Undirected`: All edges from or to `a`. |
| /// |
| /// Produces an empty iterator if the node doesn't exist.<br> |
| /// Iterator element type is `(N, N, &E)`. |
| pub fn edges(&self, a: N) -> Edges<N, E, Ty> { |
| Edges { |
| from: a, |
| iter: self.neighbors(a), |
| edges: &self.edges, |
| } |
| } |
| |
| /// Return an iterator of target nodes with an edge starting from `a`, |
| /// paired with their respective edge weights. |
| /// |
| /// - `Directed`, `Outgoing`: All edges from `a`. |
| /// - `Directed`, `Incoming`: All edges to `a`. |
| /// - `Undirected`, `Outgoing`: All edges connected to `a`, with `a` being the source of each |
| /// edge. |
| /// - `Undirected`, `Incoming`: All edges connected to `a`, with `a` being the target of each |
| /// edge. |
| /// |
| /// Produces an empty iterator if the node doesn't exist.<br> |
| /// Iterator element type is `(N, N, &E)`. |
| pub fn edges_directed(&self, a: N, dir: Direction) -> EdgesDirected<N, E, Ty> { |
| EdgesDirected { |
| from: a, |
| iter: self.neighbors_directed(a, dir), |
| dir, |
| edges: &self.edges, |
| } |
| } |
| |
| /// Return a reference to the edge weight connecting `a` with `b`, or |
| /// `None` if the edge does not exist in the graph. |
| pub fn edge_weight(&self, a: N, b: N) -> Option<&E> { |
| self.edges.get(&Self::edge_key(a, b)) |
| } |
| |
| /// Return a mutable reference to the edge weight connecting `a` with `b`, or |
| /// `None` if the edge does not exist in the graph. |
| pub fn edge_weight_mut(&mut self, a: N, b: N) -> Option<&mut E> { |
| self.edges.get_mut(&Self::edge_key(a, b)) |
| } |
| |
| /// Return an iterator over all edges of the graph with their weight in arbitrary order. |
| /// |
| /// Iterator element type is `(N, N, &E)` |
| pub fn all_edges(&self) -> AllEdges<N, E, Ty> { |
| AllEdges { |
| inner: self.edges.iter(), |
| ty: self.ty, |
| } |
| } |
| |
| /// Return an iterator over all edges of the graph in arbitrary order, with a mutable reference |
| /// to their weight. |
| /// |
| /// Iterator element type is `(N, N, &mut E)` |
| pub fn all_edges_mut(&mut self) -> AllEdgesMut<N, E, Ty> { |
| AllEdgesMut { |
| inner: self.edges.iter_mut(), |
| ty: self.ty, |
| } |
| } |
| |
| /// Return a `Graph` that corresponds to this `GraphMap`. |
| /// |
| /// 1. Note that node and edge indices in the `Graph` have nothing in common |
| /// with the `GraphMap`s node weights `N`. The node weights `N` are used as |
| /// node weights in the resulting `Graph`, too. |
| /// 2. Note that the index type is user-chosen. |
| /// |
| /// Computes in **O(|V| + |E|)** time (average). |
| /// |
| /// **Panics** if the number of nodes or edges does not fit with |
| /// the resulting graph's index type. |
| pub fn into_graph<Ix>(self) -> Graph<N, E, Ty, Ix> |
| where |
| Ix: crate::graph::IndexType, |
| { |
| // assuming two successive iterations of the same hashmap produce the same order |
| let mut gr = Graph::with_capacity(self.node_count(), self.edge_count()); |
| for (&node, _) in &self.nodes { |
| gr.add_node(node); |
| } |
| for ((a, b), edge_weight) in self.edges { |
| let (ai, _, _) = self.nodes.get_full(&a).unwrap(); |
| let (bi, _, _) = self.nodes.get_full(&b).unwrap(); |
| gr.add_edge(node_index(ai), node_index(bi), edge_weight); |
| } |
| gr |
| } |
| |
| /// Creates a `GraphMap` that corresponds to the given `Graph`. |
| /// |
| /// **Warning**: Nodes with the same weight are merged and only the last parallel edge |
| /// is kept. Node and edge indices of the `Graph` are lost. Only use this function |
| /// if the node weights are distinct and there are no parallel edges. |
| /// |
| /// Computes in **O(|V| + |E|)** time (average). |
| pub fn from_graph<Ix>(graph: Graph<N, E, Ty, Ix>) -> Self |
| where |
| Ix: crate::graph::IndexType, |
| E: Clone, |
| { |
| let mut new_graph: GraphMap<N, E, Ty> = |
| GraphMap::with_capacity(graph.node_count(), graph.edge_count()); |
| |
| for node in graph.raw_nodes() { |
| new_graph.add_node(node.weight); |
| } |
| |
| for edge in graph.edge_indices() { |
| let (a, b) = graph.edge_endpoints(edge).unwrap(); |
| new_graph.add_edge( |
| *graph.node_weight(a).unwrap(), |
| *graph.node_weight(b).unwrap(), |
| graph.edge_weight(edge).unwrap().clone(), |
| ); |
| } |
| |
| new_graph |
| } |
| } |
| |
| /// Create a new `GraphMap` from an iterable of edges. |
| impl<N, E, Ty, Item> FromIterator<Item> for GraphMap<N, E, Ty> |
| where |
| Item: IntoWeightedEdge<E, NodeId = N>, |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| fn from_iter<I>(iterable: I) -> Self |
| where |
| I: IntoIterator<Item = Item>, |
| { |
| let iter = iterable.into_iter(); |
| let (low, _) = iter.size_hint(); |
| let mut g = Self::with_capacity(0, low); |
| g.extend(iter); |
| g |
| } |
| } |
| |
| /// Extend the graph from an iterable of edges. |
| /// |
| /// Nodes are inserted automatically to match the edges. |
| impl<N, E, Ty, Item> Extend<Item> for GraphMap<N, E, Ty> |
| where |
| Item: IntoWeightedEdge<E, NodeId = N>, |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| fn extend<I>(&mut self, iterable: I) |
| where |
| I: IntoIterator<Item = Item>, |
| { |
| let iter = iterable.into_iter(); |
| let (low, _) = iter.size_hint(); |
| self.edges.reserve(low); |
| |
| for elt in iter { |
| let (source, target, weight) = elt.into_weighted_edge(); |
| self.add_edge(source, target, weight); |
| } |
| } |
| } |
| |
| iterator_wrap! { |
| impl (Iterator DoubleEndedIterator ExactSizeIterator) for |
| #[derive(Debug, Clone)] |
| struct Nodes <'a, N> where { N: 'a + NodeTrait } |
| item: N, |
| iter: Cloned<Keys<'a, N, Vec<(N, CompactDirection)>>>, |
| } |
| |
| #[derive(Debug, Clone)] |
| pub struct Neighbors<'a, N, Ty = Undirected> |
| where |
| N: 'a, |
| Ty: EdgeType, |
| { |
| iter: Iter<'a, (N, CompactDirection)>, |
| ty: PhantomData<Ty>, |
| } |
| |
| impl<'a, N, Ty> Iterator for Neighbors<'a, N, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| type Item = N; |
| fn next(&mut self) -> Option<N> { |
| if Ty::is_directed() { |
| (&mut self.iter) |
| .filter_map(|&(n, dir)| if dir == Outgoing { Some(n) } else { None }) |
| .next() |
| } else { |
| self.iter.next().map(|&(n, _)| n) |
| } |
| } |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| let (lower, upper) = self.iter.size_hint(); |
| if Ty::is_directed() { |
| (0, upper) |
| } else { |
| (lower, upper) |
| } |
| } |
| } |
| |
| #[derive(Debug, Clone)] |
| pub struct NeighborsDirected<'a, N, Ty> |
| where |
| N: 'a, |
| Ty: EdgeType, |
| { |
| iter: Iter<'a, (N, CompactDirection)>, |
| start_node: N, |
| dir: Direction, |
| ty: PhantomData<Ty>, |
| } |
| |
| impl<'a, N, Ty> Iterator for NeighborsDirected<'a, N, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| type Item = N; |
| fn next(&mut self) -> Option<N> { |
| if Ty::is_directed() { |
| let self_dir = self.dir; |
| let start_node = self.start_node; |
| (&mut self.iter) |
| .filter_map(move |&(n, dir)| { |
| if dir == self_dir || n == start_node { |
| Some(n) |
| } else { |
| None |
| } |
| }) |
| .next() |
| } else { |
| self.iter.next().map(|&(n, _)| n) |
| } |
| } |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| let (lower, upper) = self.iter.size_hint(); |
| if Ty::is_directed() { |
| (0, upper) |
| } else { |
| (lower, upper) |
| } |
| } |
| } |
| |
| #[derive(Debug, Clone)] |
| pub struct Edges<'a, N, E: 'a, Ty> |
| where |
| N: 'a + NodeTrait, |
| Ty: EdgeType, |
| { |
| from: N, |
| edges: &'a IndexMap<(N, N), E>, |
| iter: Neighbors<'a, N, Ty>, |
| } |
| |
| impl<'a, N, E, Ty> Iterator for Edges<'a, N, E, Ty> |
| where |
| N: 'a + NodeTrait, |
| E: 'a, |
| Ty: EdgeType, |
| { |
| type Item = (N, N, &'a E); |
| fn next(&mut self) -> Option<Self::Item> { |
| self.iter.next().map(|b| { |
| let a = self.from; |
| match self.edges.get(&GraphMap::<N, E, Ty>::edge_key(a, b)) { |
| None => unreachable!(), |
| Some(edge) => (a, b, edge), |
| } |
| }) |
| } |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| self.iter.size_hint() |
| } |
| } |
| |
| #[derive(Debug, Clone)] |
| pub struct EdgesDirected<'a, N, E: 'a, Ty> |
| where |
| N: 'a + NodeTrait, |
| Ty: EdgeType, |
| { |
| from: N, |
| dir: Direction, |
| edges: &'a IndexMap<(N, N), E>, |
| iter: NeighborsDirected<'a, N, Ty>, |
| } |
| |
| impl<'a, N, E, Ty> Iterator for EdgesDirected<'a, N, E, Ty> |
| where |
| N: 'a + NodeTrait, |
| E: 'a, |
| Ty: EdgeType, |
| { |
| type Item = (N, N, &'a E); |
| fn next(&mut self) -> Option<Self::Item> { |
| self.iter.next().map(|mut b| { |
| let mut a = self.from; |
| if self.dir == Direction::Incoming { |
| mem::swap(&mut a, &mut b); |
| } |
| match self.edges.get(&GraphMap::<N, E, Ty>::edge_key(a, b)) { |
| None => unreachable!(), |
| Some(edge) => (a, b, edge), |
| } |
| }) |
| } |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| self.iter.size_hint() |
| } |
| } |
| |
| #[derive(Debug, Clone)] |
| pub struct AllEdges<'a, N, E: 'a, Ty> |
| where |
| N: 'a + NodeTrait, |
| { |
| inner: IndexMapIter<'a, (N, N), E>, |
| ty: PhantomData<Ty>, |
| } |
| |
| impl<'a, N, E, Ty> Iterator for AllEdges<'a, N, E, Ty> |
| where |
| N: 'a + NodeTrait, |
| E: 'a, |
| Ty: EdgeType, |
| { |
| type Item = (N, N, &'a E); |
| fn next(&mut self) -> Option<Self::Item> { |
| self.inner.next().map(|(&(a, b), v)| (a, b, v)) |
| } |
| |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| self.inner.size_hint() |
| } |
| |
| fn count(self) -> usize { |
| self.inner.count() |
| } |
| |
| fn nth(&mut self, n: usize) -> Option<Self::Item> { |
| self.inner |
| .nth(n) |
| .map(|(&(n1, n2), weight)| (n1, n2, weight)) |
| } |
| |
| fn last(self) -> Option<Self::Item> { |
| self.inner |
| .last() |
| .map(|(&(n1, n2), weight)| (n1, n2, weight)) |
| } |
| } |
| |
| impl<'a, N, E, Ty> DoubleEndedIterator for AllEdges<'a, N, E, Ty> |
| where |
| N: 'a + NodeTrait, |
| E: 'a, |
| Ty: EdgeType, |
| { |
| fn next_back(&mut self) -> Option<Self::Item> { |
| self.inner |
| .next_back() |
| .map(|(&(n1, n2), weight)| (n1, n2, weight)) |
| } |
| } |
| |
| pub struct AllEdgesMut<'a, N, E: 'a, Ty> |
| where |
| N: 'a + NodeTrait, |
| { |
| inner: IndexMapIterMut<'a, (N, N), E>, // TODO: change to something that implements Debug + Clone? |
| ty: PhantomData<Ty>, |
| } |
| |
| impl<'a, N, E, Ty> Iterator for AllEdgesMut<'a, N, E, Ty> |
| where |
| N: 'a + NodeTrait, |
| E: 'a, |
| Ty: EdgeType, |
| { |
| type Item = (N, N, &'a mut E); |
| fn next(&mut self) -> Option<Self::Item> { |
| self.inner |
| .next() |
| .map(|(&(n1, n2), weight)| (n1, n2, weight)) |
| } |
| |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| self.inner.size_hint() |
| } |
| |
| fn count(self) -> usize { |
| self.inner.count() |
| } |
| |
| fn nth(&mut self, n: usize) -> Option<Self::Item> { |
| self.inner |
| .nth(n) |
| .map(|(&(n1, n2), weight)| (n1, n2, weight)) |
| } |
| |
| fn last(self) -> Option<Self::Item> { |
| self.inner |
| .last() |
| .map(|(&(n1, n2), weight)| (n1, n2, weight)) |
| } |
| } |
| |
| impl<'a, N, E, Ty> DoubleEndedIterator for AllEdgesMut<'a, N, E, Ty> |
| where |
| N: 'a + NodeTrait, |
| E: 'a, |
| Ty: EdgeType, |
| { |
| fn next_back(&mut self) -> Option<Self::Item> { |
| self.inner |
| .next_back() |
| .map(|(&(n1, n2), weight)| (n1, n2, weight)) |
| } |
| } |
| |
| /// Index `GraphMap` by node pairs to access edge weights. |
| impl<N, E, Ty> Index<(N, N)> for GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| type Output = E; |
| fn index(&self, index: (N, N)) -> &E { |
| let index = Self::edge_key(index.0, index.1); |
| self.edge_weight(index.0, index.1) |
| .expect("GraphMap::index: no such edge") |
| } |
| } |
| |
| /// Index `GraphMap` by node pairs to access edge weights. |
| impl<N, E, Ty> IndexMut<(N, N)> for GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| fn index_mut(&mut self, index: (N, N)) -> &mut E { |
| let index = Self::edge_key(index.0, index.1); |
| self.edge_weight_mut(index.0, index.1) |
| .expect("GraphMap::index: no such edge") |
| } |
| } |
| |
| /// Create a new empty `GraphMap`. |
| impl<N, E, Ty> Default for GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| fn default() -> Self { |
| GraphMap::with_capacity(0, 0) |
| } |
| } |
| |
| /// A reference that is hashed and compared by its pointer value. |
| /// |
| /// `Ptr` is used for certain configurations of `GraphMap`, |
| /// in particular in the combination where the node type for |
| /// `GraphMap` is something of type for example `Ptr(&Cell<T>)`, |
| /// with the `Cell<T>` being `TypedArena` allocated. |
| pub struct Ptr<'b, T: 'b>(pub &'b T); |
| |
| impl<'b, T> Copy for Ptr<'b, T> {} |
| impl<'b, T> Clone for Ptr<'b, T> { |
| fn clone(&self) -> Self { |
| *self |
| } |
| } |
| |
| fn ptr_eq<T>(a: *const T, b: *const T) -> bool { |
| a == b |
| } |
| |
| impl<'b, T> PartialEq for Ptr<'b, T> { |
| /// Ptr compares by pointer equality, i.e if they point to the same value |
| fn eq(&self, other: &Ptr<'b, T>) -> bool { |
| ptr_eq(self.0, other.0) |
| } |
| } |
| |
| impl<'b, T> PartialOrd for Ptr<'b, T> { |
| fn partial_cmp(&self, other: &Ptr<'b, T>) -> Option<Ordering> { |
| Some(self.cmp(other)) |
| } |
| } |
| |
| impl<'b, T> Ord for Ptr<'b, T> { |
| /// Ptr is ordered by pointer value, i.e. an arbitrary but stable and total order. |
| fn cmp(&self, other: &Ptr<'b, T>) -> Ordering { |
| let a: *const T = self.0; |
| let b: *const T = other.0; |
| a.cmp(&b) |
| } |
| } |
| |
| impl<'b, T> Deref for Ptr<'b, T> { |
| type Target = T; |
| fn deref(&self) -> &T { |
| self.0 |
| } |
| } |
| |
| impl<'b, T> Eq for Ptr<'b, T> {} |
| |
| impl<'b, T> Hash for Ptr<'b, T> { |
| fn hash<H: hash::Hasher>(&self, st: &mut H) { |
| let ptr = (self.0) as *const T; |
| ptr.hash(st) |
| } |
| } |
| |
| impl<'b, T: fmt::Debug> fmt::Debug for Ptr<'b, T> { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| self.0.fmt(f) |
| } |
| } |
| |
| #[derive(Debug, Clone)] |
| pub struct NodeIdentifiers<'a, N, E: 'a, Ty> |
| where |
| N: 'a + NodeTrait, |
| { |
| iter: IndexMapIter<'a, N, Vec<(N, CompactDirection)>>, |
| ty: PhantomData<Ty>, |
| edge_ty: PhantomData<E>, |
| } |
| |
| impl<'a, N, E, Ty> Iterator for NodeIdentifiers<'a, N, E, Ty> |
| where |
| N: 'a + NodeTrait, |
| E: 'a, |
| Ty: EdgeType, |
| { |
| type Item = N; |
| fn next(&mut self) -> Option<Self::Item> { |
| self.iter.next().map(|(&n, _)| n) |
| } |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| self.iter.size_hint() |
| } |
| } |
| |
| #[derive(Debug, Clone)] |
| pub struct NodeReferences<'a, N, E: 'a, Ty> |
| where |
| N: 'a + NodeTrait, |
| { |
| iter: IndexMapIter<'a, N, Vec<(N, CompactDirection)>>, |
| ty: PhantomData<Ty>, |
| edge_ty: PhantomData<E>, |
| } |
| |
| impl<'a, N, E, Ty> Iterator for NodeReferences<'a, N, E, Ty> |
| where |
| N: 'a + NodeTrait, |
| E: 'a, |
| Ty: EdgeType, |
| { |
| type Item = (N, &'a N); |
| fn next(&mut self) -> Option<Self::Item> { |
| self.iter.next().map(|(n, _)| (*n, n)) |
| } |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| self.iter.size_hint() |
| } |
| } |
| |
| impl<N, E, Ty> visit::GraphBase for GraphMap<N, E, Ty> |
| where |
| N: Copy + PartialEq, |
| { |
| type NodeId = N; |
| type EdgeId = (N, N); |
| } |
| |
| impl<N, E, Ty> visit::Data for GraphMap<N, E, Ty> |
| where |
| N: Copy + PartialEq, |
| Ty: EdgeType, |
| { |
| type NodeWeight = N; |
| type EdgeWeight = E; |
| } |
| |
| impl<N, E, Ty> visit::Visitable for GraphMap<N, E, Ty> |
| where |
| N: Copy + Ord + Hash, |
| Ty: EdgeType, |
| { |
| type Map = HashSet<N>; |
| fn visit_map(&self) -> HashSet<N> { |
| HashSet::with_capacity(self.node_count()) |
| } |
| fn reset_map(&self, map: &mut Self::Map) { |
| map.clear(); |
| } |
| } |
| |
| impl<N, E, Ty> visit::GraphProp for GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| type EdgeType = Ty; |
| } |
| |
| impl<'a, N, E, Ty> visit::IntoNodeReferences for &'a GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| type NodeRef = (N, &'a N); |
| type NodeReferences = NodeReferences<'a, N, E, Ty>; |
| fn node_references(self) -> Self::NodeReferences { |
| NodeReferences { |
| iter: self.nodes.iter(), |
| ty: self.ty, |
| edge_ty: PhantomData, |
| } |
| } |
| } |
| |
| impl<'a, N, E: 'a, Ty> visit::IntoNodeIdentifiers for &'a GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| type NodeIdentifiers = NodeIdentifiers<'a, N, E, Ty>; |
| |
| fn node_identifiers(self) -> Self::NodeIdentifiers { |
| NodeIdentifiers { |
| iter: self.nodes.iter(), |
| ty: self.ty, |
| edge_ty: PhantomData, |
| } |
| } |
| } |
| |
| impl<N, E, Ty> visit::NodeCount for GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| fn node_count(&self) -> usize { |
| (*self).node_count() |
| } |
| } |
| |
| impl<N, E, Ty> visit::NodeIndexable for GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| fn node_bound(&self) -> usize { |
| self.node_count() |
| } |
| fn to_index(&self, ix: Self::NodeId) -> usize { |
| let (i, _, _) = self.nodes.get_full(&ix).unwrap(); |
| i |
| } |
| fn from_index(&self, ix: usize) -> Self::NodeId { |
| assert!( |
| ix < self.nodes.len(), |
| "The requested index {} is out-of-bounds.", |
| ix |
| ); |
| let (&key, _) = self.nodes.get_index(ix).unwrap(); |
| key |
| } |
| } |
| |
| impl<N, E, Ty> visit::NodeCompactIndexable for GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| } |
| |
| impl<'a, N: 'a, E, Ty> visit::IntoNeighbors for &'a GraphMap<N, E, Ty> |
| where |
| N: Copy + Ord + Hash, |
| Ty: EdgeType, |
| { |
| type Neighbors = Neighbors<'a, N, Ty>; |
| fn neighbors(self, n: Self::NodeId) -> Self::Neighbors { |
| self.neighbors(n) |
| } |
| } |
| |
| impl<'a, N: 'a, E, Ty> visit::IntoNeighborsDirected for &'a GraphMap<N, E, Ty> |
| where |
| N: Copy + Ord + Hash, |
| Ty: EdgeType, |
| { |
| type NeighborsDirected = NeighborsDirected<'a, N, Ty>; |
| fn neighbors_directed(self, n: N, dir: Direction) -> Self::NeighborsDirected { |
| self.neighbors_directed(n, dir) |
| } |
| } |
| |
| impl<N, E, Ty> visit::EdgeIndexable for GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| fn edge_bound(&self) -> usize { |
| self.edge_count() |
| } |
| |
| fn to_index(&self, ix: Self::EdgeId) -> usize { |
| let (i, _, _) = self.edges.get_full(&ix).unwrap(); |
| i |
| } |
| |
| fn from_index(&self, ix: usize) -> Self::EdgeId { |
| assert!( |
| ix < self.edges.len(), |
| "The requested index {} is out-of-bounds.", |
| ix |
| ); |
| let (&key, _) = self.edges.get_index(ix).unwrap(); |
| key |
| } |
| } |
| |
| impl<'a, N: 'a, E: 'a, Ty> visit::IntoEdges for &'a GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| type Edges = Edges<'a, N, E, Ty>; |
| fn edges(self, a: Self::NodeId) -> Self::Edges { |
| self.edges(a) |
| } |
| } |
| |
| impl<'a, N: 'a, E: 'a, Ty> visit::IntoEdgesDirected for &'a GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| type EdgesDirected = EdgesDirected<'a, N, E, Ty>; |
| fn edges_directed(self, a: Self::NodeId, dir: Direction) -> Self::EdgesDirected { |
| self.edges_directed(a, dir) |
| } |
| } |
| |
| impl<'a, N: 'a, E: 'a, Ty> visit::IntoEdgeReferences for &'a GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| type EdgeRef = (N, N, &'a E); |
| type EdgeReferences = AllEdges<'a, N, E, Ty>; |
| fn edge_references(self) -> Self::EdgeReferences { |
| self.all_edges() |
| } |
| } |
| |
| impl<N, E, Ty> visit::EdgeCount for GraphMap<N, E, Ty> |
| where |
| N: NodeTrait, |
| Ty: EdgeType, |
| { |
| #[inline] |
| fn edge_count(&self) -> usize { |
| self.edge_count() |
| } |
| } |
| |
| /// The `GraphMap` keeps an adjacency matrix internally. |
| impl<N, E, Ty> visit::GetAdjacencyMatrix for GraphMap<N, E, Ty> |
| where |
| N: Copy + Ord + Hash, |
| Ty: EdgeType, |
| { |
| type AdjMatrix = (); |
| #[inline] |
| fn adjacency_matrix(&self) {} |
| #[inline] |
| fn is_adjacent(&self, _: &(), a: N, b: N) -> bool { |
| self.contains_edge(a, b) |
| } |
| } |
| |
| /// A [ParallelIterator] over this graph's nodes. |
| #[cfg(feature = "rayon")] |
| pub struct ParNodes<'a, N> |
| where |
| N: Send + Sync, |
| { |
| iter: ParKeys<'a, N, Vec<(N, CompactDirection)>>, |
| } |
| |
| #[cfg(feature = "rayon")] |
| impl<'a, N> ParallelIterator for ParNodes<'a, N> |
| where |
| N: Send + Sync, |
| { |
| type Item = &'a N; |
| |
| fn drive_unindexed<C>(self, c: C) -> C::Result |
| where |
| C: UnindexedConsumer<Self::Item>, |
| { |
| self.iter.drive_unindexed(c) |
| } |
| } |