Skip to content

Caching Adjacency Matrix for faster edge lookup #344

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
ZigRazor merged 11 commits into from
Sep 25, 2023
Merged

Caching Adjacency Matrix for faster edge lookup #344

Show file tree
Hide file tree
Changes from 7 commits
Commits
Show all changes
11 commits
Select commit Hold shift + click to select a range
c69ccf7
Added changes to save nodes in Dijkstra shortest path. Modified tests.
guru2396 Aug 28, 2023
8fca1dc
Merge branch 'ZigRazor:master' into master
guru2396 Sep 6, 2023
d4aa31d
Merge branch 'ZigRazor:master' into master
guru2396 Sep 14, 2023
62f0597
Caching adjacency matrix for faster edge lookup
guru2396 Sep 14, 2023
f97818c
Merge branch 'master' of https://github.com/guru2396/CXXGraph
guru2396 Sep 14, 2023
0454d53
changing return type of getCacheAdjMatrix(), using alias for shared_ptr
guru2396 Sep 15, 2023
38e47d7
using alias for shared_ptr, removing unused vars
guru2396 Sep 17, 2023
842d796
Merge branch 'ZigRazor:master' into master
guru2396 Sep 23, 2023
6b85303
added more tests for findEdge()
guru2396 Sep 23, 2023
72b124e
added more tests for findEdge()
guru2396 Sep 23, 2023
d3815b9
renaming function, adding spaces
guru2396 Sep 24, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
104 changes: 99 additions & 5 deletions include/Graph/Graph.hpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -101,6 +101,8 @@ class Graph {
private:
T_EdgeSet<T> edgeSet = {};

shared<AdjacencyMatrix<T>> cachedAdjMatrix;

// Private non-const getter for the set of nodes
std::unordered_set<shared<Node<T>>, nodeHash<T>> nodeSet();

Expand Down Expand Up @@ -130,7 +132,7 @@ class Graph {
#endif

public:
Graph() = default;
Graph();
Graph(const T_EdgeSet<T> &edgeSet);
virtual ~Graph() = default;
/**
Expand Down Expand Up @@ -248,7 +250,9 @@ class Graph {
* corrispondent to the link
* Note: No Thread Safe
*/
virtual const std::shared_ptr<AdjacencyMatrix<T>> getAdjMatrix() const;
virtual shared<AdjacencyMatrix<T>> getAdjMatrix() const;

virtual void getCacheAdjMatrix();
/**
* \brief This function generates a set of nodes linked to the provided node
* in a directed graph
Expand Down Expand Up @@ -733,11 +737,19 @@ class Graph {
const AdjacencyMatrix<T> &adj);
};

template <typename T>
Graph<T>::Graph() {
/* Caching the adjacency matrix */
getCacheAdjMatrix();
}

template <typename T>
Graph<T>::Graph(const T_EdgeSet<T> &edgeSet) {
for (auto edgeIt : edgeSet) {
this->edgeSet.insert(edgeIt);
}
/* Caching the adjacency matrix */
getCacheAdjMatrix();
}

template <typename T>
Expand All @@ -751,6 +763,8 @@ void Graph<T>::setEdgeSet(const T_EdgeSet<T> &edgeSet) {
for (auto edgeIt : edgeSet) {
this->edgeSet.insert(edgeIt);
}
/* Caching the adjacency matrix */
getCacheAdjMatrix();
}

template <typename T>
Expand All @@ -759,24 +773,47 @@ void Graph<T>::addEdge(const Edge<T> *edge) {
if (edge->isWeighted().has_value() && edge->isWeighted().value()) {
auto edge_shared = make_shared<DirectedWeightedEdge<T>>(*edge);
this->edgeSet.insert(edge_shared);
std::pair<shared<const Node<T>>, shared<const Edge<T>>> elem = {edge_shared->getNodePair().second, edge_shared};
(*cachedAdjMatrix)[edge_shared->getNodePair().first].push_back(std::move(elem));
} else {
auto edge_shared = make_shared<DirectedEdge<T>>(*edge);
this->edgeSet.insert(edge_shared);
std::pair<shared<const Node<T>>, shared<const Edge<T>>> elem = {edge_shared->getNodePair().second, edge_shared};
(*cachedAdjMatrix)[edge_shared->getNodePair().first].push_back(std::move(elem));
}
} else {
if (edge->isWeighted().has_value() && edge->isWeighted().value()) {
auto edge_shared = make_shared<UndirectedWeightedEdge<T>>(*edge);
this->edgeSet.insert(edge_shared);
std::pair<shared<const Node<T>>, shared<const Edge<T>>> elem = {edge_shared->getNodePair().second, edge_shared};
(*cachedAdjMatrix)[edge_shared->getNodePair().first].push_back(std::move(elem));
std::pair<shared<const Node<T>>, shared<const Edge<T>>> elem1 = {edge_shared->getNodePair().first, edge_shared};
(*cachedAdjMatrix)[edge_shared->getNodePair().second].push_back(std::move(elem1));
} else {
auto edge_shared = make_shared<UndirectedEdge<T>>(*edge);
this->edgeSet.insert(edge_shared);
std::pair<shared<const Node<T>>, shared<const Edge<T>>> elem = {edge_shared->getNodePair().second, edge_shared};
(*cachedAdjMatrix)[edge_shared->getNodePair().first].push_back(std::move(elem));
std::pair<shared<const Node<T>>, shared<const Edge<T>>> elem1 = {edge_shared->getNodePair().first, edge_shared};
(*cachedAdjMatrix)[edge_shared->getNodePair().second].push_back(std::move(elem1));
}
}
}

template <typename T>
void Graph<T>::addEdge(shared<const Edge<T>> edge) {
this->edgeSet.insert(edge);
/* Adding new edge in cached adjacency matrix */
if(edge.get()->isDirected().has_value() && edge.get()->isDirected().value()){
std::pair<shared<const Node<T>>, shared<const Edge<T>>> elem = {edge.get()->getNodePair().second, edge};
(*cachedAdjMatrix)[edge.get()->getNodePair().first].push_back(std::move(elem));
}
else{
std::pair<shared<const Node<T>>, shared<const Edge<T>>> elem = {edge.get()->getNodePair().second, edge};
(*cachedAdjMatrix)[edge.get()->getNodePair().first].push_back(std::move(elem));
std::pair<shared<const Node<T>>, shared<const Edge<T>>> elem1 = {edge.get()->getNodePair().first, edge};
(*cachedAdjMatrix)[edge.get()->getNodePair().second].push_back(std::move(elem1));
}
}

template <typename T>
Expand All @@ -788,6 +825,32 @@ void Graph<T>::removeEdge(const unsigned long long edgeId) {
[edgeOpt](const Edge<T> *edge) { return (*(edgeOpt.value()) == *edge); }));
*/
edgeSet.erase(edgeSet.find(edgeOpt.value()));
int delIndex = -1;
int i = 0;
/* Removing the edge from the cached adjacency matrix */
for(auto elem : (*cachedAdjMatrix)[edgeOpt.value().get()->getNodePair().first]){
if(elem.second.get()->getId() == edgeId){
delIndex = i;
break;
}
i++;
}
if(delIndex != -1){
(*cachedAdjMatrix)[edgeOpt.value().get()->getNodePair().first].erase((*cachedAdjMatrix)[edgeOpt.value().get()->getNodePair().first].begin()+delIndex);
}

delIndex = -1;
i = 0;
for(auto elem : (*cachedAdjMatrix)[edgeOpt.value().get()->getNodePair().second]){
if(elem.second.get()->getId() == edgeId){
delIndex = i;
break;
}
i++;
}
if(delIndex != -1){
(*cachedAdjMatrix)[edgeOpt.value().get()->getNodePair().second].erase((*cachedAdjMatrix)[edgeOpt.value().get()->getNodePair().second].begin()+delIndex);
}
}
}

Expand All @@ -805,7 +868,32 @@ bool Graph<T>::findEdge(shared<const Node<T>> v1, shared<const Node<T>> v2,
unsigned long long &id) const {
// This could be made faster by looking for the edge hash, assuming we hash
// based on node data, instead of a unique integer
for (auto e : this->edgeSet) {
if(cachedAdjMatrix.get() != NULL){
/* Searching for the edge using cached adjacency matrix */

for(auto elem : (*cachedAdjMatrix)[v1]){
if(elem.first == v2){
id = elem.second.get()->getId();
return true;
}
}
}
else{
/* Searching for the edge using edgeset */

for (auto e : this->edgeSet) {
if ((e->getNodePair().first == v1) && (e->getNodePair().second == v2)) {
id = e->getId();
return true;
}
if (!e->isDirected() &&
((e->getNodePair().second == v1) && (e->getNodePair().first == v2))) {
id = e->getId();
return true;
}
}
}
/*for (auto e : this->edgeSet) {
if ((e->getNodePair().first == v1) && (e->getNodePair().second == v2)) {
id = e->getId();
return true;
Expand All @@ -815,7 +903,7 @@ bool Graph<T>::findEdge(shared<const Node<T>> v1, shared<const Node<T>> v2,
id = e->getId();
return true;
}
}
}*/

id = 0;
return false;
Expand Down Expand Up @@ -1381,7 +1469,7 @@ std::shared_ptr<std::vector<Node<T>>> Graph<T>::eulerianPath() const {
}

template <typename T>
const std::shared_ptr<AdjacencyMatrix<T>> Graph<T>::getAdjMatrix() const {
shared<AdjacencyMatrix<T>> Graph<T>::getAdjMatrix() const {
auto adj = std::make_shared<AdjacencyMatrix<T>>();
auto addElementToAdjMatrix = [&adj](shared<const Node<T>> nodeFrom,
shared<const Node<T>> nodeTo,
Expand Down Expand Up @@ -1413,6 +1501,12 @@ const std::shared_ptr<AdjacencyMatrix<T>> Graph<T>::getAdjMatrix() const {
return adj;
}

template <typename T>
void Graph<T>::getCacheAdjMatrix() {
const auto adj = Graph<T>::getAdjMatrix();
this->cachedAdjMatrix = adj;
}

template <typename T>
const std::unordered_set<shared<const Node<T>>, nodeHash<T>>
Graph<T>::outNeighbors(const Node<T> *node) const {
Expand Down
27 changes: 27 additions & 0 deletions test/GraphTest.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -105,6 +105,33 @@ TEST(GraphTest, GetNodeSet_2) {
}) != nodeSet.end());
}

TEST(GraphTest, FindEdge_Test) {
Copy link
Collaborator

@nrkramer nrkramer Sep 23, 2023

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Please add spacing in logical places between lines in this test. It's hard to read

Copy link
Contributor Author

@guru2396 guru2396 Sep 24, 2023

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Done. Please review.

CXXGraph::Node<int> node1("1", 1);
CXXGraph::Node<int> node2("2", 2);
CXXGraph::Node<int> node3("3", 3);
CXXGraph::Node<int> node4("4", 2);
CXXGraph::Node<int> node5("5", 3);
CXXGraph::UndirectedEdge<int> edge(1, node1, node2);
CXXGraph::UndirectedEdge<int> edge2(2, node2, node3);
CXXGraph::T_EdgeSet<int> edgeSet;
edgeSet.insert(make_shared<CXXGraph::UndirectedEdge<int>>(edge));
edgeSet.insert(make_shared<CXXGraph::UndirectedEdge<int>>(edge2));
CXXGraph::Graph<int> graph(edgeSet);
unsigned long long edgeId = 0;
ASSERT_TRUE(graph.findEdge(&node1,&node2,edgeId));
CXXGraph::UndirectedEdge<int> edge3(3, node1, node3);
graph.addEdge(make_shared<CXXGraph::UndirectedEdge<int>>(edge3));
ASSERT_TRUE(graph.findEdge(&node1,&node3,edgeId));
ASSERT_TRUE(graph.findEdge(&node3,&node1,edgeId));
CXXGraph::DirectedEdge<int> edge4(4, node1, node5);
graph.addEdge(make_shared<CXXGraph::DirectedEdge<int>>(edge4));
ASSERT_TRUE(graph.findEdge(&node1,&node5,edgeId));
ASSERT_FALSE(graph.findEdge(&node5,&node1,edgeId));
graph.removeEdge(2);
ASSERT_FALSE(graph.findEdge(&node2,&node3,edgeId));
ASSERT_FALSE(graph.findEdge(&node3,&node2,edgeId));
}

TEST(GraphTest, RawAddEdge_1) {
CXXGraph::Node<int> n1("a", 1);
CXXGraph::Node<int> n2("b", 1);
Expand Down