C++ TNodeI::GetDeg方法代码示例

// Save and load directed, undirected and multi-graphs as list of edges, where nodes are ids
void SaveLoadEdgeList() {
  
  const int NNodes = 500;
  const int NEdges = 2000;
  
  const char *FName = "demo.graph.dat";
  const char *Desc = "Randomly generated graph for input/output.";
  
  PNGraph GOut, GIn;
  GOut = GenRndGnm<PNGraph>(NNodes, NEdges);
  
  // Output node IDs as numbers
  SaveEdgeList(GOut, FName, Desc);
  
  // Load edge list
  GIn = LoadEdgeList<PNGraph>(FName);
  
  // Verify all nodes exist in input and output graphs
  THashSet<TInt> OutNIdH, InNIdH;
  
  for (TNGraph::TNodeI NI = GOut->BegNI(); NI < GOut->EndNI(); NI++) {
    // Nodes that do not have edges are left off during input
    if (NI.GetDeg() > 0) {
      OutNIdH.AddKey(NI.GetId());
    }
  }
  for (TNGraph::TNodeI NI = GIn->BegNI(); NI < GIn->EndNI(); NI++) {
    InNIdH.AddKey(NI.GetId());
  }
  
  PrintGStats<PNGraph>("EdgeList - Out", GOut);
  PrintGStats<PNGraph>("EdgeList - In", GIn);
  
}

// Saves and loads a graph in a MATLAB sparse matrix format
void IOMatlabSparseMtx() {
  
  const int NNodes = 500;
  const int NEdges = 2000;
  
  const char *FName = "demo.matlab.dat";
  
  PNGraph GOut, GIn;
  GOut = GenRndGnm<PNGraph>(NNodes, NEdges);
  
  SaveMatlabSparseMtx(GOut, FName);
  
  GIn = TNGraph::New();
  GIn->Reserve(NNodes, NEdges);
  
  // Read-in Matlab-file
  FILE *F = fopen(FName, "r");
  while (! feof(F)) {
    int Src, Dst, Edge;
    fscanf(F, "%d %d %d\n", &Src, &Dst, &Edge);
    Src--; Dst--;             // SNAP graphs start at Node Ids of 0
    if (not GIn->IsNode(Src)) {
      GIn->AddNode(Src);
    }
    if (not GIn->IsNode(Dst)) {
      GIn->AddNode(Dst);
    }
    GIn->AddEdge(Src, Dst);
    
  }
  fclose(F);
  
  // Verify all nodes exist in input and output graphs (and no more)
  THashSet<TInt> OutNIdH, InNIdH;
  
  for (TNGraph::TNodeI NI = GOut->BegNI(); NI < GOut->EndNI(); NI++) {
    // Nodes that do not have edges are left off during input
    if (NI.GetDeg() > 0) {
      OutNIdH.AddKey(NI.GetId());
    }
  }
  for (TNGraph::TNodeI NI = GIn->BegNI(); NI < GIn->EndNI(); NI++) {
    InNIdH.AddKey(NI.GetId());
  }
  PrintGStats("Matlab - Out", GOut);
  PrintGStats("Matlab - In", GIn);
    
}

// Rok #13
//template<class PGraph> 
int64 CountTriangles1(const TVec<TNGraph::TNodeI,int>& NV, const TIntV& IndV, const TIntV& MapV) {
  struct timeval start, end;
  float delta;
  TTmProfiler Profiler;
  int TimerId = Profiler.AddTimer("Profiler");

  int ind = MapV.Len();

  Profiler.ResetTimer(TimerId);
  Profiler.StartTimer(TimerId);
  gettimeofday(&start, NULL);

  TVec<TIntV> HigherDegNbrV(ind);

  for (int i = 0; i < ind; i++) {
    HigherDegNbrV[i] = TVec<TInt>();
    HigherDegNbrV[i].Reserve(NV[i].GetDeg());
    HigherDegNbrV[i].Reduce(0);
  }

  gettimeofday(&end, NULL);
  Profiler.StopTimer(TimerId);
  delta = ((end.tv_sec  - start.tv_sec) * 1000000u +
            end.tv_usec - start.tv_usec) / 1.e6;
  printf("__valloc__\ttime %7.3f\tcpu %8.3f\n", delta, Profiler.GetTimerSec(TimerId));

  Profiler.ResetTimer(TimerId);
  Profiler.StartTimer(TimerId);
  gettimeofday(&start, NULL);

#pragma omp parallel for schedule(dynamic)
  for (TInt i = 0; i < ind; i++) {
    TNGraph::TNodeI NI = NV[i];
    //HigherDegNbrV[i] = TVec<TInt>();
    //HigherDegNbrV[i].Reserve(NI.GetDeg());
    //HigherDegNbrV[i].Reduce(0);

    GetMergeSortedV(HigherDegNbrV[i], NI);

    int k = 0;
    for (TInt j = 0; j < HigherDegNbrV[i].Len(); j++) {
      TInt Vert = HigherDegNbrV[i][j];
      TInt Deg = NV[IndV[Vert]].GetDeg();
      if (Deg > NI.GetDeg() ||
         (Deg == NI.GetDeg() && Vert > NI.GetId())) {
        HigherDegNbrV[i][k] = Vert;
        k++;
      }
    }
    HigherDegNbrV[i].Reduce(k);
  }

  gettimeofday(&end, NULL);
  Profiler.StopTimer(TimerId);
  delta = ((end.tv_sec  - start.tv_sec) * 1000000u +
            end.tv_usec - start.tv_usec) / 1.e6;
  printf("__sort__\ttime %7.3f\tcpu %8.3f\n", delta, Profiler.GetTimerSec(TimerId));

  Profiler.ResetTimer(TimerId);
  Profiler.StartTimer(TimerId);
  gettimeofday(&start, NULL);

  int64 cnt = 0;
#pragma omp parallel for schedule(dynamic) reduction(+:cnt)
  for (TInt i = 0; i < HigherDegNbrV.Len(); i++) {
    for (TInt j = 0; j < HigherDegNbrV[i].Len(); j++) {
      //TInt NbrInd = H.GetDat(HigherDegNbrV[i][j]);
      TInt NbrInd = IndV[HigherDegNbrV[i][j]];

      int64 num = GetCommon(HigherDegNbrV[i], HigherDegNbrV[NbrInd]);
      cnt += num;
    }
  }

  gettimeofday(&end, NULL);
  Profiler.StopTimer(TimerId);
  delta = ((end.tv_sec  - start.tv_sec) * 1000000u +
            end.tv_usec - start.tv_usec) / 1.e6;
  printf("__count__\ttime %7.3f\tcpu %8.3f\n", delta, Profiler.GetTimerSec(TimerId));

  return cnt;
}

int64 CountTriangles2(const PNGraph &Graph) {
  struct timeval start, end;
  float delta;
  TTmProfiler Profiler;
  int TimerId = Profiler.AddTimer("Profiler");
  const int NNodes = Graph->GetNodes();

  TIntV MapV(NNodes);
  TVec<TNGraph::TNodeI> NV(NNodes);
  NV.Reduce(0);

  Profiler.ResetTimer(TimerId);
  Profiler.StartTimer(TimerId);
  gettimeofday(&start, NULL);

  int MxId = -1;
  int ind = 0;
  for (TNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++)   {
    NV.Add(NI);
    int Id = NI.GetId();
    if (Id > MxId) {
      MxId = Id;
    }
    MapV[ind] = Id;
    ind++;
  }

  TIntV IndV(MxId+1);

  for (int j = 0; j < NNodes; j++) {
    IndV[MapV[j]] = j;
  }

  gettimeofday(&end, NULL);
  Profiler.StopTimer(TimerId);
  delta = ((end.tv_sec  - start.tv_sec) * 1000000u +
          end.tv_usec - start.tv_usec) / 1.e6;
  printf("__nodemap__\ttime %7.3f\tcpu %8.3f\n", delta, Profiler.GetTimerSec(TimerId));

  Profiler.ResetTimer(TimerId);
  Profiler.StartTimer(TimerId);
  gettimeofday(&start, NULL);

  ind = MapV.Len();

  Profiler.ResetTimer(TimerId);
  Profiler.StartTimer(TimerId);
  gettimeofday(&start, NULL);

  TVec<TIntV> HigherDegNbrV(ind);

  for (int i = 0; i < ind; i++) {
    HigherDegNbrV[i] = TVec<TInt>();
    HigherDegNbrV[i].Reserve(NV[i].GetDeg());
    HigherDegNbrV[i].Reduce(0);
  }

  gettimeofday(&end, NULL);
  Profiler.StopTimer(TimerId);
  delta = ((end.tv_sec  - start.tv_sec) * 1000000u +
            end.tv_usec - start.tv_usec) / 1.e6;
  printf("__valloc__\ttime %7.3f\tcpu %8.3f\n", delta, Profiler.GetTimerSec(TimerId));

  Profiler.ResetTimer(TimerId);
  Profiler.StartTimer(TimerId);
  gettimeofday(&start, NULL);

#pragma omp parallel for schedule(dynamic)
  for (TInt i = 0; i < ind; i++) {
    TNGraph::TNodeI NI = NV[i];
    //HigherDegNbrV[i] = TVec<TInt>();
    //HigherDegNbrV[i].Reserve(NI.GetDeg());
    //HigherDegNbrV[i].Reduce(0);

    GetMergeSortedV(HigherDegNbrV[i], NI);

    int k = 0;
    for (TInt j = 0; j < HigherDegNbrV[i].Len(); j++) {
      TInt Vert = HigherDegNbrV[i][j];
      TInt Deg = NV[IndV[Vert]].GetDeg();
      if (Deg > NI.GetDeg() ||
         (Deg == NI.GetDeg() && Vert > NI.GetId())) {
        HigherDegNbrV[i][k] = Vert;
        k++;
      }
    }
    HigherDegNbrV[i].Reduce(k);
  }

  gettimeofday(&end, NULL);
  Profiler.StopTimer(TimerId);
  delta = ((end.tv_sec  - start.tv_sec) * 1000000u +
            end.tv_usec - start.tv_usec) / 1.e6;
  printf("__sort__\ttime %7.3f\tcpu %8.3f\n", delta, Profiler.GetTimerSec(TimerId));

  Profiler.ResetTimer(TimerId);
  Profiler.StartTimer(TimerId);
  gettimeofday(&start, NULL);

  int64 cnt = 0;
//.........这里部分代码省略.........

// Test node, edge creation
TEST(TNGraph, ManipulateNodesEdges) {
  int NNodes = 10000;
  int NEdges = 100000;
  const char *FName = "test.graph.dat";

  PNGraph Graph;
  PNGraph Graph1;
  PNGraph Graph2;
  int i;
  int n;
  int NCount;
  int x,y;
  int Deg, InDeg, OutDeg;

  Graph = TNGraph::New();
  EXPECT_EQ(1,Graph->Empty());

  // create the nodes
  for (i = 0; i < NNodes; i++) {
    Graph->AddNode(i);
  }
  EXPECT_EQ(0,Graph->Empty());
  EXPECT_EQ(NNodes,Graph->GetNodes());

  // create random edges
  NCount = NEdges;
  while (NCount > 0) {
    x = (long) (drand48() * NNodes);
    y = (long) (drand48() * NNodes);
    // Graph->GetEdges() is not correct for the loops (x == y),
    // skip the loops in this test
    if (x != y  &&  !Graph->IsEdge(x,y)) {
      n = Graph->AddEdge(x, y);
      NCount--;
    }
  }

  EXPECT_EQ(NEdges,Graph->GetEdges());

  EXPECT_EQ(0,Graph->Empty());
  EXPECT_EQ(1,Graph->IsOk());

  for (i = 0; i < NNodes; i++) {
    EXPECT_EQ(1,Graph->IsNode(i));
  }

  EXPECT_EQ(0,Graph->IsNode(NNodes));
  EXPECT_EQ(0,Graph->IsNode(NNodes+1));
  EXPECT_EQ(0,Graph->IsNode(2*NNodes));

  // nodes iterator
  NCount = 0;
  for (TNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
    NCount++;
  }
  EXPECT_EQ(NNodes,NCount);

  // edges per node iterator
  NCount = 0;
  for (TNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
    for (int e = 0; e < NI.GetOutDeg(); e++) {
      NCount++;
    }
  }
  EXPECT_EQ(NEdges,NCount);

  // edges iterator
  NCount = 0;
  for (TNGraph::TEdgeI EI = Graph->BegEI(); EI < Graph->EndEI(); EI++) {
    NCount++;
  }
  EXPECT_EQ(NEdges,NCount);

  // node degree
  for (TNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
    Deg = NI.GetDeg();
    InDeg = NI.GetInDeg();
    OutDeg = NI.GetOutDeg();

    EXPECT_EQ(Deg,InDeg+OutDeg);
  }

  // assignment
  Graph1 = TNGraph::New();
  *Graph1 = *Graph;

  EXPECT_EQ(NNodes,Graph1->GetNodes());
  EXPECT_EQ(NEdges,Graph1->GetEdges());
  EXPECT_EQ(0,Graph1->Empty());
  EXPECT_EQ(1,Graph1->IsOk());

  // saving and loading
  {
    TFOut FOut(FName);
    Graph->Save(FOut);
    FOut.Flush();
  }

  {
//.........这里部分代码省略.........