1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386
//! # Topology
//! Implements a network.
//!
//! You probably want to take a look at the struct [`GenericGraph`](crate::GenericGraph),
//! since it contains the topology information.
//!
//! For Erdős-Rényi Graphs, see struct `ER`
use crate::{traits::*, GraphErrors, GenericGraph};
use std::marker::PhantomData;
use std::convert::From;
#[cfg(feature = "serde_support")]
use serde::{Serialize, Deserialize};
/// # Used for accessing neighbor information from graph
/// * contains Adjacency list
/// and internal id (normally the index in the graph).
/// * also contains user specified data, i.e, `T` from `NodeContainer<T>`
/// * see trait **`AdjContainer`**
#[derive(Debug, Clone)]
#[cfg_attr(feature = "serde_support", derive(Serialize, Deserialize))]
pub struct NodeContainer<T: Node>{
id: usize,
pub(crate) adj: Vec<usize>,
node: T,
}
impl<T: Node + SerdeStateConform> AdjContainer<T> for NodeContainer<T> {
/// Create new instance with id
fn new(id: usize, node: T) -> Self {
NodeContainer{
id,
adj: Vec::new(),
node,
}
}
/// return reference to what the NodeContainer contains
fn contained(&self) -> &T {
&self.node
}
/// return mut reference to what the NodeContainer contains
fn contained_mut(&mut self) -> &mut T {
&mut self.node
}
/// returns iterator over indices of neighbors
fn neighbors(&self) -> IterWrapper {
IterWrapper::new_generic(self.adj.iter())
}
/// count number of neighbors, i.e. number of edges incident to `self`
fn degree(&self) -> usize {
self.adj.len()
}
/// returns id of container
/// ## Note:
/// (in `Graph<T>`: `id` equals the index corresponding to `self`)
fn id(&self) -> usize {
self.id
}
/// check if vertex with `other_id` is adjacent to self
/// ## Note:
/// (in `Graph<T>`: `id` equals the index corresponding to `self`)
fn is_adjacent(&self, other_id: usize) -> bool {
self.adj.contains(&other_id)
}
/// # Sorting adjecency lists
/// * calls `sort_unstable()` on all adjecency lists
fn sort_adj(&mut self) {
self.adj.sort_unstable();
}
#[doc(hidden)]
unsafe fn clear_edges(&mut self) {
self.adj.clear();
}
#[doc(hidden)]
unsafe fn push(&mut self, other: &mut Self)
-> Result<(), GraphErrors>
{
if self.is_adjacent(other.id()) {
return Err(GraphErrors::EdgeExists);
}
self.adj.push(other.id());
other.adj.push(self.id);
Ok(())
}
/// Tries to remove edges, returns error `GraphErrors::EdgeDoesNotExist` if impossible
#[doc(hidden)]
unsafe fn remove(&mut self, other: &mut Self)
-> Result<(), GraphErrors>
{
if !self.is_adjacent(other.id()){
return Err(GraphErrors::EdgeDoesNotExist);
}
self.swap_remove_element(other.id());
other.swap_remove_element(self.id());
Ok(())
}
fn get_adj_first(&self) -> Option<&usize> {
self.adj.first()
}
}
impl<T: Node> NodeContainer<T> {
fn swap_remove_element(&mut self, elem: usize) {
let index = self.adj
.iter()
.position(|&x| x == elem)
.expect("swap_remove_element ERROR 0");
self.adj
.swap_remove(index);
}
}
/// # Contains the topology and **implements functions** for analyzing topology
/// used for graph ensembles
/// # Example:
/// A graph, where each node stores a phase
/// ```
/// use net_ensembles::{Graph, Node, AdjContainer};
/// use net_ensembles::traits::DotExtra;
///
/// use std::fs::File;
///
/// // Note: feature "serde_support" is enabled on default
/// #[cfg(feature = "serde_support")]
/// use serde_json;
/// #[cfg(feature = "serde_support")]
/// use serde::{Serialize, Deserialize};
///
/// // define your own vertices, if you need to store extra information at each vertex
/// // if you do not use the feature "serde_support", you do not need to derive Serialize and Deserialize
/// #[derive(Debug, Clone)]
/// #[cfg_attr(feature = "serde_support", derive(Serialize, Deserialize))]
/// pub struct PhaseNode {phase: f64,}
///
/// // implement whatever you need
/// impl PhaseNode {
/// pub fn set_phase(&mut self, phase: f64) {
/// self.phase = phase;
/// }
///
/// pub fn get_phase(&self) -> f64 {
/// self.phase
/// }
/// }
///
/// // implement the trait `Node`
/// impl Node for PhaseNode {
/// fn new_from_index(index: usize) -> Self {
/// PhaseNode { phase: index as f64 * 10.0}
/// }
///
/// }
///
/// // now you can create an empty graph
/// let mut graph: Graph<PhaseNode> = Graph::new(4);
/// for i in 0..4 {
/// assert_eq!(
/// graph.at(i).get_phase(),
/// i as f64 * 10.0
/// );
/// }
///
/// // and fill it with edges
/// for i in 0..4 {
/// graph.add_edge(i, (i + 1) % 4).unwrap();
/// }
///
///
/// // you can manipulate the extra information stored at each Vertex
/// for i in 0..4 {
/// graph.at_mut(i).set_phase(i as f64 * 0.5);
/// }
///
/// // you can, of course, also access the information
/// for i in 0..4 {
/// assert_eq!(
/// graph.at(i).get_phase(),
/// i as f64 * 0.5
/// );
/// }
///
/// // if you want to visualize your graph, you can generate a file with graphviz representation
/// let mut f = File::create("phase_example.dot").expect("Unable to create file");
/// graph.dot_from_contained_index(
/// f,
/// "",
/// |index, contained|
/// format!(
/// "Phase: {} at index {}",
/// contained.get_phase(),
/// index
/// )
/// ).unwrap();
///
/// // storing the graph only works, if the feature "serde_support" is enabled (enabled by default)
/// #[cfg(feature = "serde_support")]
/// {
/// let mut graph_file = File::create("store_graph_example.dat")
/// .expect("Unable to create file");
/// let s = serde_json::to_writer_pretty(graph_file, &graph).unwrap();
///
/// // loading stored graph:
/// let mut read_in = File::open("store_graph_example.dat")
/// .expect("Unable to open file");
///
///
/// let graph2: Graph<PhaseNode> = serde_json::from_reader(read_in).unwrap();
///
///
/// // now, to show, that the graphs are equal, here is one of my test functions:
/// // modified for this example, which is a doc-test, so this example also serves as unit test
///
/// fn assert_equal_graphs(g1: &Graph<PhaseNode>, g2: &Graph<PhaseNode>) {
/// assert_eq!(g1.edge_count(), g2.edge_count());
/// assert_eq!(g1.vertex_count(), g2.vertex_count());
/// for (n0, n1) in g2.container_iter().zip(g1.container_iter()) {
/// assert_eq!(n1.id(), n0.id());
/// assert_eq!(n0.degree(), n1.degree());
///
/// for (i, j) in n1.neighbors().zip(n0.neighbors()) {
/// assert_eq!(i, j);
/// }
/// }
///
/// for i in 0..g2.vertex_count() {
/// assert_eq!(
/// g1.at(i).get_phase(),
/// g2.at(i).get_phase()
/// );
/// }
/// }
///
/// // lets use it
/// assert_equal_graphs(&graph, &graph2);
///
/// // you can also clone the graph, if you need:
/// let clone = graph.clone();
/// assert_equal_graphs(&graph, &clone);
/// let clone2 = graph2.clone();
/// assert_equal_graphs(&clone, &clone2);
/// }
///
/// ```
/// `phase_example.dot` will contain
/// ```dot
/// graph G{
///
/// 0 1 2 3 ;
/// "0" [label="Phase: 0 at index 0"];
/// "1" [label="Phase: 0.5 at index 1"];
/// "2" [label="Phase: 1 at index 2"];
/// "3" [label="Phase: 1.5 at index 3"];
/// 0 -- 1
/// 0 -- 3
/// 1 -- 2
/// 2 -- 3
/// }
/// ```
/// Now you can use `circo` or similar programs to create a pdf from that.
/// Search for **graphviz** for more info.
pub type Graph<T> = GenericGraph<T, NodeContainer<T>>;
impl<T> Graph<T>
where T: Node
{
/// Efficiently create a complete graph with n nodes
pub fn complete_graph(n: usize) -> Self
{
let mut vertices = Vec::with_capacity(n);
for i in 0..n {
let mut adj = Vec::with_capacity(n - 1);
adj.extend(0..i);
adj.extend((i+1)..n);
vertices.push(
NodeContainer{
id: i,
node: T::new_from_index(i),
adj,
}
)
}
Self{
next_id: n,
edge_count: n*(n - 1) / 2,
vertices,
phantom: PhantomData::<T>,
}
}
pub(crate) fn reset_from_graph(&mut self, other: &Self)
{
assert!(other.vertex_count() <= self.vertex_count());
self.clear_edges();
for i in 0..other.vertex_count(){
self.vertices[i].adj.extend_from_slice(other.vertices[i].adj.as_slice());
}
self.edge_count = other.edge_count;
}
}
impl<T: Node, A: AdjContainer<T>> From<&GenericGraph<T, A>> for Graph<T>
{
fn from(source: &GenericGraph<T, A>) -> Self
{
// efficiently convert
let vertices = source
.container_iter()
.map(|container|
NodeContainer{
id: container.id(),
node: container.contained().clone(),
adj: container.neighbors().copied().collect(),
}
).collect();
Self{
next_id: source.next_id,
edge_count: source.edge_count(),
vertices,
phantom: PhantomData::<T>,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::EmptyNode;
#[test]
fn test_graph_container_push() {
// create two nodes
let mut c = NodeContainer::new(0, EmptyNode::new_from_index(0));
let mut c2 = NodeContainer::new(1, EmptyNode::new_from_index(1));
// create edge -> should not result in error!
let res = unsafe { c.push(&mut c2) };
if let Err(e) = res {
panic!("error: {}", e);
}
// now edge exists, should not be able to add it again:
let res = unsafe { c.push(&mut c2) };
assert!(res.is_err());
assert_eq!(0, c.id());
}
#[test]
fn correct_complete_graphs() {
let g = Graph::<EmptyNode>::complete_graph(50);
for index in 0..50 {
let container = g.container(index);
for neigbor in 0..50 {
if neigbor == index {
assert!(!container.is_adjacent(neigbor));
} else {
assert!(container.is_adjacent(neigbor));
}
}
}
assert_eq!(g.vertex_count(), 50);
}
}