Feat: accept gml as input file

Chore: included make_graphs and make_planar

.README

@@ -0,0 +1,3 @@
+Deferred Planarity Test implementation is from
+https://code.google.com/archive/p/planarity-algorithms/. The original code is
+licensed under the "New BSD License".

.gitignore

@@ -1,2 +1,6 @@
 .vscode
 deferred_planarity_test/bin
+make_graphs/bin
+make_graphs/test_graphs
+make_planar/bin
+test_area

deferred_planarity_test/main.cpp

@@ -3,33 +3,14 @@
 //-----------------------------------------------------------------------------------
 
 #include <iostream>
-#include <fstream>
 #include <cstdlib>
 #include <climits>
+#include <string>
 #include "mps.h"
 using namespace std;
 
-void find_mps(ifstream*, ofstream*);
+int find_mps(string input_file);
 
-//n nodes, with the probability of existence of each edge being p.
-void random_graph_generator(int n, double p, ofstream* out) {
-	(*out) << n << endl;
-	for (int i = 0; i < n; ++i) {
-		for (int j = i+1; j < n; ++j) {
-			if ((double)rand()/RAND_MAX <= p) (*out) << i << " " << j << endl;
-		}
-	}
-}
-
-//Complete graph K_n.
-void complete_graph_generator(int n, ofstream* out) {
-	(*out) << n << endl;
-	for (int i = 0; i < n; ++i) {
-		for (int j = i+1; j < n; ++j) {
-			(*out) << i << " " << j << endl;
-		}
-	}
-}
 
 //-----------------------------------------------------------------------------------
 // Main function.
@@ -37,34 +18,8 @@ void complete_graph_generator(int n, ofstream* out) {
 
 
 int main(int argc, char* argv[]) {
-	if (argc == 1) {
+    string input_file = argv[1];
-		cout << "Usages:" << endl;
+	std::cout << "Number of removed edges: " << find_mps(input_file) << std::endl;
-		cout << "======================" << endl;
+
-		cout << "mps_testing -mps <infile> <outfile>" << endl;
-		cout << "  Process the infile, and output the resulting maximal" << endl
-			 << "  planar subgraph in the outfile." << endl;
-		cout << "mps_testing -gen <infile> <outfile>" << endl;
-		cout << "  Generate a random graph as the spec given in the infile." << endl;
-		while (true) {
-			int x = 0;
-			cin >> x;
-		}
-	}
-	ifstream in;
-	in.open(argv[2]);
-	ofstream out;
-	out.open(argv[3]);
-	if (!in.is_open() || !out.is_open()) {
-		cout << "An error occurs when opening file." << endl;
-		return 0;
-	}
-	if (argv[1][1] == 'm') find_mps(&in, &out);
-	else if (argv[1][1] == 'g') {
-		int n;
-		double p;
-		in >> n;
-		in >> p;
-		random_graph_generator(n, p, &out);
-	}
 	return 0;
 }

deferred_planarity_test/mps.h

@@ -141,11 +141,10 @@ class maximal_planar_subgraph_finder
 public:
 	maximal_planar_subgraph_finder();
 	~maximal_planar_subgraph_finder();
-	void find_mps(ifstream* in, ofstream* out);
+	int find_mps(string input_file);
 	node* get_new_node(node_type t);
-	void read_from_file(ifstream* in);
+    void read_from_gml(string input_file);
-	void output(ofstream* out);
+	int output_removed_edge_size();
-	void output_deleted_edges(ofstream* out);
 	void postOrderTraversal();
 	void sort_adj_list();
 	void determine_edges();

deferred_planarity_test/mps_test.cpp

@@ -3,62 +3,61 @@
 //-----------------------------------------------------------------------------------
 
 #include "mps.h"
+#include <ogdf/fileformats/GraphIO.h>
 
 //-----------------------------------------------------------------------------------
 // Finding MPS
 //-----------------------------------------------------------------------------------
-void find_mps(ifstream* in, ofstream* out) {
+int find_mps(string input_file) {
 	maximal_planar_subgraph_finder m;
-	m.find_mps(in, out);
+	return m.find_mps(input_file);
 }
 
-void maximal_planar_subgraph_finder::find_mps(ifstream* in, ofstream* out) {
+int maximal_planar_subgraph_finder::find_mps(string input_file) {
-	read_from_file(in);
+	read_from_gml(input_file);
 	postOrderTraversal();
 	sort_adj_list();
 	determine_edges();
 	back_edge_traversal();
-	output(out);
+	return output_removed_edge_size();
 }
 
 //-----------------------------------------------------------------------------------
 // Imput, output
 //-----------------------------------------------------------------------------------
-//First line: a single integer indicates the number of nodes.
+
-//The rest: a pair of integers (i, j) represents an edge (i, j)
+
-//0 <= i, j < n-1, where n is number of nodes.
+// read input file of gml format
-void maximal_planar_subgraph_finder::read_from_file(ifstream* in) {
+void maximal_planar_subgraph_finder::read_from_gml(string input_file) {
-	int node_num, n1, n2;
+    ogdf::Graph G;
-    //Number of nodes.
+
-	(*in) >> node_num;
+    // utilize OGDF readGML
-    //initialize all the nodes.
+    if (!ogdf::GraphIO::read(G, input_file, ogdf::GraphIO::readGML)) {
-	for (int i = 0; i < node_num; ++i) {
+        std::cerr << "Could not read " << input_file << ".gml" << std::endl;
+    }
+
+    // create nodes
+	for (int i = 0; i < G.numberOfNodes(); ++i) {
 		_node_list.push_back(new node(P_NODE));
 		_node_list[i]->set_id(i);
 	}
-	//Set the adj-list.
+
-	while ((*in) >> n1 >> n2) {
+    // create edges
-		_node_list[n1]->add_adj(_node_list[n2]);
+    for (ogdf::edge e : G.edges) {
-		_node_list[n2]->add_adj(_node_list[n1]);
+        ogdf::node source = e->source();
-	}
+        ogdf::node target = e->target();
+        _node_list[source->index()]->add_adj(_node_list[target->index()]);
+        _node_list[target->index()]->add_adj(_node_list[source->index()]);
+    }
 }
 
+
+
 //Output a maximal planar subgraph in the same format as input.
-void maximal_planar_subgraph_finder::output(ofstream* out) {
+int maximal_planar_subgraph_finder::output_removed_edge_size() {
-	(*out) << _node_list.size() << endl;
+    int sum = 0;
-	for (int i = 0; i < _edge_list.size(); ++i) {
+    for (int i = 0; i < _back_edge_list.size(); ++i) {
-		(*out) << _edge_list[i].first->node_id() << " " <<  _edge_list[i].second->node_id() << endl;
+		if (_is_back_edge_eliminate[i]) ++sum; 
-	}
+    }
-	for (int i = 0; i < _back_edge_list.size(); ++i) {
+    return sum;
-		if (_is_back_edge_eliminate[i]) continue;
+}
-		(*out) << _back_edge_list[i].first->node_id() << " " <<  _back_edge_list[i].second->node_id() << endl;
-	}
-}
-
-void maximal_planar_subgraph_finder::output_deleted_edges(ofstream* out) {
-	(*out) << _node_list.size() << endl;
-	for (int i = 0; i < _back_edge_list.size(); ++i) {
-		if (!_is_back_edge_eliminate[i]) continue;
-		(*out) << _back_edge_list[i].first->node_id() << " " <<  _back_edge_list[i].second->node_id() << endl;
-	}
-}

make_graphs/make_graphs.cpp

@@ -0,0 +1,32 @@
+#include <ogdf/basic/basic.h>
+#include <ogdf/basic/Graph.h>
+#include <ogdf/fileformats/GraphIO.h>
+#include <ogdf/basic/graph_generators.h>
+
+using namespace ogdf;
+
+int main(int argc, char **argv) {
+    int nodeCount = std::stoi(argv[1]);
+    int edgeCount = std::stoi(argv[2]);
+    int copies = std::stoi(argv[3]);
+    int seed = std::stoi(argv[4]);
+    bool enforcePlanar = std::stoi(argv[5]);
+    std::string outputFolder = argv[6];
+
+    setSeed(seed);
+    for (int i = 0; i < copies; i++) {
+        Graph G;
+        if (enforcePlanar) {
+            randomPlanarBiconnectedGraph(G, nodeCount, edgeCount, false);
+        } else {
+            randomBiconnectedGraph(G, nodeCount, edgeCount);
+        }
+
+        std::stringstream ss;
+        ss << outputFolder << "/graphn" << nodeCount << "e" << edgeCount << "s" << seed << "i" << i
+           << (enforcePlanar ? "planar" : "") << ".gml";
+        std::string s = ss.str();
+        GraphIO::write(G, s, GraphIO::writeGML);
+    }
+
+}

make_planar/make_planar.cpp

@@ -0,0 +1,328 @@
+#include <PCTree/PCTree.h>
+
+// #include "hsuPC/include/PCTree.h"
+// #include "hsuPC/include/PCNode.h"
+
+#include <ogdf/basic/STNumbering.h>
+#include <ogdf/basic/graph_generators.h>
+#include <ogdf/basic/GraphCopy.h>
+#include <ogdf/fileformats/GraphIO.h>
+#include <ogdf/planarity/BoothLueker.h>
+#include <ogdf/planarity/BoyerMyrvold.h>
+#include <ogdf/basic/extended_graph_alg.h>
+
+#include <ogdf/planarity/booth_lueker/IndInfo.h>
+#include <ogdf/planarity/booth_lueker/PlanarPQTree.h>
+#include <ogdf/planarity/planar_subgraph_fast/PlanarSubgraphPQTree.h>
+#include <ogdf/planarity/PlanarSubgraphFast.h>
+#include <ogdf/planarity/PlanarSubgraphBoyerMyrvold.h>
+#include <ogdf/planarity/PlanarSubgraphPC.h>
+#include <ogdf/planarity/MaximumPlanarSubgraph.h>
+#include <ogdf/planarity/MaximalPlanarSubgraphSimple.h>
+
+#include <iostream>
+#include <map>
+#include <chrono>
+#include <getopt.h>
+
+using namespace ogdf;
+
+using std::chrono::time_point;
+using std::chrono::high_resolution_clock;
+using std::chrono::duration_cast;
+using std::chrono::nanoseconds;
+
+
+void planarizePQ(const Graph &G, NodeArray<int> &numbering, List<edge> &delEdges) {
+		using PlanarLeafKey = booth_lueker::PlanarLeafKey<whaInfo*>;
+
+		NodeArray<SListPure<PlanarLeafKey*>> inLeaves(G);
+		NodeArray<SListPure<PlanarLeafKey*>> outLeaves(G);
+		Array<node> table(G.numberOfNodes()+1);
+
+		for(node v : G.nodes) {
+			for(adjEntry adj : v->adjEntries) {
+				edge e = adj->theEdge();
+				if (numbering[e->opposite(v)] > numbering[v]) { // sideeffect: ignores selfloops
+					PlanarLeafKey* L = new PlanarLeafKey(e);
+					inLeaves[v].pushFront(L);
+				}
+			}
+			table[numbering[v]] = v;
+		}
+
+		for(node v : G.nodes) {
+			for (PlanarLeafKey *L : inLeaves[v]) {
+				outLeaves[L->userStructKey()->opposite(v)].pushFront(L);
+			}
+		}
+
+		SList<PQLeafKey<edge,whaInfo*,bool>*> totalEliminatedKeys;
+
+		PlanarSubgraphPQTree T;
+		T.Initialize(inLeaves[table[1]]);
+		for (int i = 2; i < G.numberOfNodes(); i++) {
+			SList<PQLeafKey<edge,whaInfo*,bool>*> eliminatedKeys; // handle key elimination
+			T.Reduction(outLeaves[table[i]], eliminatedKeys); // handle key elimination
+			totalEliminatedKeys.conc(eliminatedKeys); // handle key elimination
+			T.ReplaceRoot(inLeaves[table[i]]);
+			T.emptyAllPertinentNodes();
+		}
+
+		// append eliminated edges to delEdges
+		for (PQLeafKey<edge, whaInfo*, bool> *key : totalEliminatedKeys) {
+			edge e = key->userStructKey();
+			delEdges.pushBack(e);
+		}
+
+		//cleanup
+		for(node v : G.nodes) {
+			while (!inLeaves[v].empty()) {
+				PlanarLeafKey *L = inLeaves[v].popFrontRet();
+				delete L;
+			}
+		}
+
+		T.Cleanup();	// Explicit call for destructor necessary. This allows to call virtual
+		// function CleanNode for freeing node information class.
+	}
+
+
+template<typename PCT, typename PCN, typename PCNT>
+void planarizePC(const Graph &G, const NodeArray<int> &numbering, List<edge> &delEdges) {
+    // initialize PCTree instance
+    PCT T;
+
+    // vector to store nodes of graph in order specified in numbering
+    std::vector<node> order(G.numberOfNodes(), nullptr);
+    for (node n : G.nodes) {
+        order.at(numbering[n] - 1) = n;
+    }
+
+    // store leaf representations of edges in PCTree
+    std::vector<PCN *> leafRepresentation(G.maxEdgeIndex() + 1, nullptr);
+    // vectors declared for later use
+    std::vector<edge> outEdges;
+    std::vector<PCN *> consecutiveLeaves;
+
+    // iterates over nodes in the 'order' vector
+    for (node n : order) {
+        // quit condition: if current node is last node 
+        if (n == order[G.numberOfNodes() - 1]) {
+            break;
+        }
+
+        // clear both vectors in for each node in iteration
+        consecutiveLeaves.clear();
+        outEdges.clear();
+
+        // leafToEdge
+        // create a map of PCN to edge
+        std::map<PCN *, edge> leafToEdge;
+
+            // iterate over adjacent entries of current node
+            for (adjEntry adj : n->adjEntries)
+        {
+            // check if opposite node has higher numbering (belong to later node)
+            // add to outEdges
+            if (numbering[adj->theEdge()->opposite(n)] > numbering[n]) {
+                outEdges.push_back(adj->theEdge());
+            // add to consecutiveLeaves otherwise (declared earlier)
+            // leafRepresentation will be filled later on
+            } else {
+                consecutiveLeaves.push_back(leafRepresentation[adj->theEdge()->index()]);
+                // use leafToEdge to map leafRep object to edge object
+                // then store the edge in a collection
+                // <- insert code here ->
+                leafToEdge[leafRepresentation[adj->theEdge()->index()]] = adj->theEdge();
+
+
+            }
+        }
+
+        PCN *mergedLeaf;
+        // If first node, new P-node is created
+        if (n == order[0]) {
+            mergedLeaf = T.newNode(PCNT::PNode);
+        // consecutive leaves are merged
+        } else {
+            // T.makeConsecutive 
+            // the function returns a boolean for success
+            // I think it checks if its possible to make consecutive 
+
+            // IMPORTANT HERE
+            // here we can identify edges that result in non-planarity
+            if (!T.makeConsecutive(consecutiveLeaves)){
+
+                // keep trying different combinations until is passes
+                std::vector<PCN *> goodLeaves;
+                for (PCN* leaf: consecutiveLeaves) {
+                    goodLeaves.push_back(leaf);
+                    if (T.makeConsecutive(goodLeaves)) {
+                        continue;
+                    } else {
+                        goodLeaves.pop_back();
+                        delEdges.pushBack(leafToEdge[leaf]);
+                    } 
+                }
+                consecutiveLeaves.clear();
+                consecutiveLeaves.insert(consecutiveLeaves.end(),
+                                         goodLeaves.begin(), 
+                                         goodLeaves.end());
+                
+
+                // for rejected leaves, 
+                // return false;
+            }
+            // remove all consecutive leaves except the first
+            // returns a single leaf
+            // second argument is "assumeConsecutive", which makeConsecutive checks
+            mergedLeaf = T.mergeLeaves(consecutiveLeaves, true);
+        }
+
+        OGDF_ASSERT(!outEdges.empty());
+
+        // if there is more than 1 outEdge
+        if (outEdges.size() > 1) {
+            // clear and re-use consecutiveLeaves variable
+            consecutiveLeaves.clear(); 
+            // make a reference variabled
+            std::vector<PCN *> &addedLeaves = consecutiveLeaves;
+
+            // if mergedLeaf if a P-node
+            // PCTree_construction::insertLeaves
+            if (mergedLeaf->getNodeType() == PCNT::PNode) {
+                T.insertLeaves(outEdges.size(), mergedLeaf, &addedLeaves);
+            // otherwise mergedLeaf is a Leaf node
+            // PCTree_construction::replaceLeaf 
+            } else {
+                OGDF_ASSERT(mergedLeaf->getNodeType() == PCNT::Leaf);
+                T.replaceLeaf(outEdges.size(), mergedLeaf, &addedLeaves);
+            }
+
+            // leaf representations are updated accordingly
+            for (int i = 0; i < outEdges.size(); i++) {
+                leafRepresentation[outEdges[i]->index()] = addedLeaves[i];
+            }
+        // if there is only 1 edge
+        // first outEdge is updated to mergedLeaf node
+        } else {
+            leafRepresentation[outEdges.front()->index()] = mergedLeaf;
+        }
+    }
+
+}
+
+
+
+int main(int argc, char* argv[]) 
+{
+
+    string inputFile = argv[1];
+    string selection = argv[2];
+    string planarity = argv[3];
+    Graph G;
+
+    if (!GraphIO::read(G, inputFile, GraphIO::readGML)) {
+        std::cerr << "Could not read input.gml" << std::endl;
+        return 1;
+    }
+
+    int b;
+    std::istringstream(planarity) >> b;
+
+    if (b) {
+        // create map from integer to node
+        // find edge and change its attribute
+        // implicit assumption that nodes retain order as given by input
+        std::unordered_map<int, ogdf::node> nodeMap;
+        // Add nodes to the graph and map them to integers
+        int index = 0; 
+        for (ogdf::node v : G.nodes) {
+            nodeMap[index] = v;
+            ++index;
+        }
+
+        // manually add our own random edges
+        int numEdgesToAdd = b; // Number of edges to add
+        int count = 0;
+        std::srand(150); // Seed the random number generator
+        int numNodes = G.numberOfNodes();
+
+        while (count < numEdgesToAdd) {
+            int sourceIndex = std::rand() % numNodes; // Random source node index
+            int targetIndex = std::rand() % numNodes; // Random target node index
+
+            if (sourceIndex == targetIndex) continue;
+            ogdf::edge targetEdge = G.searchEdge(nodeMap[sourceIndex], nodeMap[targetIndex], false);
+            if (targetEdge == nullptr) {
+                G.newEdge(nodeMap[sourceIndex], nodeMap[targetIndex]);
+                std::cout << sourceIndex << ", " << targetIndex << std::endl;
+                ++count;
+            }
+        }
+    }
+    
+    NodeArray<int> numbering(G);
+    // int num = computeSTNumbering(G, numbering, 0);
+    int num = computeSTNumbering(G, numbering, nullptr, nullptr, true);
+    OGDF_ASSERT(num == G.numberOfNodes());
+
+    // print after input
+    // graphPrinter(G);
+    std::cout << "G Planarity: " << ogdf::isPlanar(G) << std::endl;
+    std::cout << "Original number of nodes: " << G.numberOfNodes() << std::endl;
+    std::cout << "Original number of edges: " << G.numberOfEdges() << std::endl;
+
+    // separator for planarization
+    // <-------------->
+
+    // PQ implementation to make planar subgraph
+    std::cout << "start planarization" << std::endl;
+    List<edge> *delEdges = new List<edge>; // empty list
+    // changed to PC
+    if (selection == "pc") {
+        planarizePC<pc_tree::PCTree, pc_tree::PCNode, pc_tree::PCNodeType>(G, numbering, *delEdges);
+    } else if (selection == "pq") {
+        planarizePQ(G, numbering, *delEdges);
+    // } else if (selection == "bm") {
+    //     SubgraphPlanarizer *crossMin = new SubgraphPlanarizer;
+    //     crossMin->call(G)
+    } else if (selection == "fast") {
+        // PlanarSubgraphModule<int> *ps = new PlanarSubgraphFast<int>;
+        // ogdf::MaximalPlanarSubgraphSimple<int> mps(*(new PlanarSubgraphBoyerMyrvold));
+        ogdf::MaximalPlanarSubgraphSimple<int> mps(*(new PlanarSubgraphFast<int>));
+        mps.call(G, *delEdges);
+
+    } else {
+        std::cout << "running maximum" << std::endl;
+        ogdf::MaximumPlanarSubgraph<int> mps;
+        mps.call(G, *delEdges);
+    }
+
+    std::cout << "Edges removed:" << delEdges->size() << std::endl;
+
+    for (edge e: *delEdges) {
+        // print removed edges
+        std::cout << e->adjSource() << std::endl;
+        G.delEdge(e);
+    }
+
+
+    GraphIO::write(G, "output.gml", GraphIO::writeGML);
+    
+
+    // edgeListPrinter(*delEdges);
+    // std::cout << std::endl;
+    // std::cout << "subG planarity: " << ogdf::isPlanar(subgraph) << std::endl;
+    std::cout << "G planarity: " << ogdf::isPlanar(G) << std::endl;
+    std::cout << "Original number of nodes: " << G.numberOfNodes() << std::endl;
+    std::cout << "Subgraph number of edges: " << G.numberOfEdges() << std::endl;
+    // graphPrinter(G);
+    // std::cout << isPlanarPC<pc_tree::hsu::PCTree, pc_tree::hsu::PCNode, pc_tree::hsu::PCTree::PCNodeType>(G, numbering) << std::endl;
+    // bool result = isPlanarPC<pc_tree::PCTree, pc_tree::PCNode, pc_tree::PCNodeType>(subG, numbering);
+    // std::cout << result << std::endl;
+
+
+    return 0;
+}