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#[cfg(feature = "serde_support")]
use serde::{Serialize, Deserialize};
use crate::{traits::*, graph::*, iter::*, GenericGraph};
use std::{borrow::*, convert::*, iter, iter::*};
use rand::seq::*;
use std::mem;
#[derive(Debug, Clone)]
#[cfg_attr(feature = "serde_support", derive(Serialize, Deserialize))]
pub struct ConfigurationModel<T, R>
where T: Node
{
graph: Graph<T>,
degree_vec: Vec<usize>,
rng: R,
random_edge_halfs: Vec<usize>,
random_edge_halfs_backup: Vec<usize>,
}
impl<T, R> ConfigurationModel<T, R>
where T: Node,
{
pub fn degree_vec(&self) -> &Vec<usize>
{
&self.degree_vec
}
}
impl<T, R> ConfigurationModel<T, R>
where T: Node,
R: rand::Rng
{
pub fn from_const(constant: usize, size: usize, rng: R) -> Option<Self>
{
if constant >= size - 1 || size * constant % 2 != 0 {
None
} else {
Some(
Self::from_vec_unchecked(
vec![constant; size]
, rng
)
)
}
}
pub fn from_generic_graph<T1, A1>(generic_graph: &GenericGraph<T1, A1>, rng: R) -> Self
where T1: Node,
A1: AdjContainer<T1>
{
Self::from_vec_unchecked(generic_graph.degree_vec(), rng)
}
pub fn clone_from_generic_graph<A>(generic_graph: &GenericGraph<T, A>, rng: R) -> Self
where T: Clone,
A: AdjContainer<T>
{
let graph = Graph::from(generic_graph);
let mut res = Self{
graph,
degree_vec: generic_graph.degree_vec(),
rng,
random_edge_halfs: Vec::new(),
random_edge_halfs_backup: Vec::new(),
};
res.init_edge_halfs();
res
}
pub fn from_vec(degree_vec: Vec<usize>, rng: R) -> Option<Self>
{
if Self::degree_vec_is_valid(°ree_vec){
Some(Self::from_vec_unchecked(degree_vec, rng))
} else {
None
}
}
pub fn from_vec_unchecked(degree_vec: Vec<usize>, rng: R) -> Self
{
let graph = Graph::<T>::new(degree_vec.len());
let mut res = Self{
graph,
degree_vec,
rng,
random_edge_halfs: Vec::new(),
random_edge_halfs_backup: Vec::new(),
};
res.init_edge_halfs();
res.randomize();
res
}
pub fn degree_vec_is_valid(degree_vec: &Vec<usize>) -> bool
{
if degree_vec.len() <= 1 {
return false;
}
if !degree_vec.iter()
.all(|°ree| degree < degree_vec.len() - 1)
{
return false;
}
let mut sum = 0;
for val in degree_vec.iter().copied()
{
sum += val;
}
sum % 2 == 0
}
pub fn assert_degree_vec_valid(degree_vec: &Vec<usize>){
assert!(
degree_vec.len() > 1,
"degree vec has to have lenght grater than 1"
);
assert!(
degree_vec.iter()
.all(|°ree| degree < degree_vec.len() - 1),
"Impossible degree vec - not enough vertices for at least on of the requested degrees"
);
let mut sum = 0;
for val in degree_vec.iter().copied()
{
sum += val;
}
assert!(
sum % 2 == 0,
"Sum of degree vec has to be even, otherwise there would be a dangling edge half, which is invalid"
);
}
pub fn swap_degree_vec(&mut self, new_degree_vec: Vec<usize>) -> Vec<usize>
{
Self::assert_degree_vec_valid(&new_degree_vec);
self.swap_degree_vec_unchecked(new_degree_vec)
}
pub fn swap_degree_vec_unchecked(&mut self, mut new_degree_vec: Vec<usize>) -> Vec<usize>
{
assert_eq!(self.degree_vec.len(), new_degree_vec.len(),
"degree_vecs need the same length"
);
mem::swap(&mut self.degree_vec, &mut new_degree_vec);
self.init_edge_halfs();
self.randomize();
new_degree_vec
}
pub fn degree_vec_from_generic_graph<T1, A1>(&mut self, generic_graph: &GenericGraph<T1, A1>)
where T1: Node,
A1: AdjContainer<T1>
{
assert_eq!(self.degree_vec.len(), generic_graph.vertices.len());
for i in 0..self.degree_vec.len(){
self.degree_vec[i] = generic_graph.vertices[i].degree();
}
self.init_edge_halfs();
self.randomize();
}
fn init_edge_halfs(&mut self)
{
self.random_edge_halfs_backup.clear();
let ptr = self.degree_vec.as_ptr();
let len = self.degree_vec.len();
self.random_edge_halfs_backup.extend(
(0..len)
.flat_map(
|i|
{
let times: usize = unsafe { *ptr.add(i)};
iter::repeat(i).take(times)
}
)
);
}
}
impl<T, R> AsRef<Graph<T>> for ConfigurationModel<T, R>
where T: Node
{
#[inline]
fn as_ref(&self) -> &Graph<T>{
&self.graph
}
}
impl<T, R> Borrow<Graph<T>> for ConfigurationModel<T, R>
where T: Node
{
#[inline]
fn borrow(&self) -> &Graph<T> {
&self.graph
}
}
impl<T, R> HasRng<R> for ConfigurationModel<T, R>
where T: Node,
R: rand::Rng,
{
fn rng(&mut self) -> &mut R {
&mut self.rng
}
fn swap_rng(&mut self, rng: &mut R) {
std::mem::swap(&mut self.rng, rng);
}
}
impl<T, R> GraphIteratorsMut<T, Graph<T>, NodeContainer<T>> for ConfigurationModel<T, R>
where T: Node
{
fn contained_iter_neighbors_mut(&mut self, index: usize) ->
NContainedIterMut<T, NodeContainer<T>>
{
self.graph.contained_iter_neighbors_mut(index)
}
fn contained_iter_neighbors_mut_with_index(&mut self, index: usize)
-> INContainedIterMut<'_, T, NodeContainer<T>>
{
self.graph.contained_iter_neighbors_mut_with_index(index)
}
fn contained_iter_mut(&mut self) -> ContainedIterMut<T, NodeContainer<T>> {
self.graph.contained_iter_mut()
}
}
impl<T, R> WithGraph<T, Graph<T>> for ConfigurationModel<T, R>
where T: Node,
{
fn at(&self, index: usize) -> &T{
self.graph.at(index)
}
fn at_mut(&mut self, index: usize) -> &mut T{
self.graph.at_mut(index)
}
fn graph(&self) -> &Graph<T> {
self.borrow()
}
fn sort_adj(&mut self) {
self.graph.sort_adj();
}
}
impl<T, R> SimpleSample for ConfigurationModel<T, R>
where T: Node,
R: rand::Rng,
{
fn randomize(&mut self) {
self.graph.clear_edges();
self.random_edge_halfs_backup.shuffle(&mut self.rng);
self.random_edge_halfs.clear();
self.random_edge_halfs.extend_from_slice(&self.random_edge_halfs_backup);
while self.random_edge_halfs.len() > 0 {
let added = self.add_multiple_random_edges();
if !added {
self.random_edge_halfs_backup.shuffle(&mut self.rng);
self.random_edge_halfs.clear();
self.random_edge_halfs.extend_from_slice(&self.random_edge_halfs_backup);
self.graph.clear_edges();
}
}
}
}
impl<T, R> ConfigurationModel<T, R>
where T: Node,
R: rand::Rng,
{
fn add_multiple_random_edges(&mut self) -> bool
{
let mut node1 = self.random_edge_halfs.pop().unwrap();
let mut counter = self.random_edge_halfs.len() - 1;
loop {
if node1 == self.random_edge_halfs[counter]{
counter = match counter.checked_sub(1){
Some(val) => val,
None => break false,
};
continue;
}
let node2 = self.random_edge_halfs.swap_remove(counter);
if self.graph
.add_edge(node1, node2)
.is_err()
{
return false;
}
if self.random_edge_halfs.len() > 1 {
node1 = self.random_edge_halfs.pop().unwrap();
counter = self.random_edge_halfs.len() - 1;
}else{
break true;
}
}
}
}
#[derive(Debug, Clone, Copy)]
#[cfg_attr(feature = "serde_support", derive(Serialize, Deserialize))]
pub enum ConfigurationModelStep {
Error,
Added((usize, usize), (usize, usize)),
}
#[derive(Debug, Clone)]
#[cfg_attr(feature = "serde_support", derive(Serialize, Deserialize))]
pub enum UndoStepErrorCM {
UnableToAddEdge((usize, usize), GraphErrors),
UnableToRemoveEdge((usize, usize), GraphErrors)
}
impl<T, R> MarkovChain<ConfigurationModelStep, Result<(), UndoStepErrorCM>> for ConfigurationModel<T, R>
where T: Node + SerdeStateConform,
R: rand::Rng,
{
fn m_step(&mut self) -> ConfigurationModelStep {
let mut vertex_list = Vec::with_capacity(2);
while vertex_list.len() < 2 {
vertex_list.extend(self.random_edge_halfs_backup.choose_multiple(&mut self.rng, 2));
if vertex_list[0] == vertex_list[1]
{
vertex_list.clear();
}
}
let edge_1: (usize, usize) = (vertex_list[0], *self.graph.vertices[vertex_list[0]].adj.choose(&mut self.rng).unwrap());
let edge_2: (usize, usize) = (vertex_list[1], *self.graph.vertices[vertex_list[1]].adj.choose(&mut self.rng).unwrap());
if edge_2.0 == edge_1.0 || edge_1.1 == edge_2.1 {
return ConfigurationModelStep::Error;
}
match self.graph.add_edge(edge_1.0, edge_2.0)
{
Err(..) => return ConfigurationModelStep::Error,
_ => ()
};
match self.graph.add_edge(edge_1.1, edge_2.1){
Err(..) => {
self.graph.remove_edge(edge_1.0, edge_2.0).unwrap();
return ConfigurationModelStep::Error
},
_ => ()
};
self.graph.remove_edge(edge_1.0, edge_1.1).expect("Fatal error in removing edges");
self.graph.remove_edge(edge_2.0, edge_2.1).expect("Fatal error in removing edges");
return ConfigurationModelStep::Added(edge_1, edge_2)
}
fn undo_step(&mut self, step: &ConfigurationModelStep) -> Result<(), UndoStepErrorCM> {
let (edge1, edge2) = match step {
ConfigurationModelStep::Error => return Ok(()),
ConfigurationModelStep::Added(edge1, edge2) => (edge1, edge2)
};
match self.graph.add_edge(edge2.0, edge2.1) {
Err(error) => return Err(UndoStepErrorCM::UnableToAddEdge(*edge2, error)),
Ok(..) => {
match self.graph.add_edge(edge1.0, edge1.1) {
Err(error) => {
self.graph.remove_edge(edge2.0, edge2.1).unwrap();
return Err(UndoStepErrorCM::UnableToAddEdge(*edge1, error))
},
Ok(..) => {
match self.graph.remove_edge(edge1.1, edge2.1){
Err(error) => {
self.graph.remove_edge(edge2.0, edge2.1).unwrap();
self.graph.remove_edge(edge1.0, edge1.1).unwrap();
return Err(UndoStepErrorCM::UnableToRemoveEdge((edge1.1, edge2.1), error))
},
Ok(..) =>{
match self.graph.remove_edge(edge1.0, edge2.0)
{
Err(error) => {
self.graph.remove_edge(edge2.0, edge2.1).unwrap();
self.graph.remove_edge(edge1.0, edge1.1).unwrap();
self.graph.add_edge(edge1.1, edge2.1).unwrap();
return Err(UndoStepErrorCM::UnableToRemoveEdge((edge1.0, edge2.0), error))
},
Ok(..) => Ok(())
}
}
}
}
}
}
}
}
fn undo_step_quiet(&mut self, step: &ConfigurationModelStep) {
let (edge1, edge2) = match step {
ConfigurationModelStep::Error => return,
ConfigurationModelStep::Added(edge1, edge2) => (edge1, edge2)
};
self.graph.add_edge(edge2.0, edge2.1).unwrap();
self.graph.add_edge(edge1.0, edge1.1).unwrap();
self.graph.remove_edge(edge1.1, edge2.1).unwrap();
self.graph.remove_edge(edge1.0, edge2.0).unwrap();
}
}
impl<T, R> Contained<T> for ConfigurationModel<T, R>
where T: Node
{
fn get_contained(&self, index: usize) -> Option<&T> {
self.graph.get_contained(index)
}
fn get_contained_mut(&mut self, index: usize) -> Option<&mut T> {
self.graph.get_contained_mut(index)
}
unsafe fn get_contained_unchecked(&self, index: usize) -> &T {
self.graph.get_contained_unchecked(index)
}
unsafe fn get_contained_unchecked_mut(&mut self, index: usize) -> &mut T {
self.graph.get_contained_unchecked_mut(index)
}
}
#[cfg(test)]
mod testing {
use super::*;
use rand_pcg::Pcg64;
use crate::*;
use rand::SeedableRng;
#[test]
fn impossible_degree_distribution() {
let rng = Pcg64::seed_from_u64(12);
let degree_vec = vec![1,2,3];
assert!(ConfigurationModel::<EmptyNode, _>::from_vec(degree_vec, rng).is_none());
}
#[test]
fn assert_degree_vec() {
let mut rng = Pcg64::seed_from_u64(12);
let mut sw: SwEnsemble<EmptyNode, _> = SwEnsemble::new(1000, 0.1, Pcg64::from_rng(&mut rng).unwrap());
let mut ensemble: ConfigurationModel<EmptyNode, _>
= ConfigurationModel::from_generic_graph(sw.graph(), Pcg64::from_rng(&mut rng).unwrap());
for i in 0..5 {
if i != 0 {
sw.randomize();
ensemble.degree_vec_from_generic_graph(sw.graph());
}
for j in 0..5 {
if j != 0 {
ensemble.randomize();
}
assert_eq!(&ensemble.graph().degree_vec(), ensemble.degree_vec());
}
}
}
#[test]
fn degree_distribution_is_valids()
{
let mut rng = Pcg64::seed_from_u64(12322);
let degree_vec = vec![1,2,3,1,2,3];
let ensemble: ConfigurationModel<EmptyNode, _>
= ConfigurationModel::from_vec(degree_vec.clone(), Pcg64::from_rng(&mut rng).unwrap()).unwrap();
for i in 0..ensemble.vertex_count()
{
assert_eq!(ensemble.graph().degree(i), Some(degree_vec[i]));
}
let sw: SwEnsemble<EmptyNode, _> = SwEnsemble::new(1000, 0.1, Pcg64::from_rng(&mut rng).unwrap());
let degree_vec: Vec<_> = sw.container_iter().map(|c| c.degree()).collect();
let ensemble: ConfigurationModel<EmptyNode, _>
= ConfigurationModel::from_vec(degree_vec.clone(), Pcg64::from_rng(&mut rng).unwrap()).unwrap();
for i in 0..ensemble.vertex_count()
{
assert_eq!(ensemble.graph().degree(i), Some(degree_vec[i]));
}
}
}