C++ PUNGraph::BegNI方法代码示例

int ComputeKCore(const PUNGraph& G) {
  int cnt = 0;
  for(TUNGraph::TNodeI NI = G->BegNI(); NI < G->EndNI(); NI++)
    cnt = max(cnt, NI.GetOutDeg());
  THashSet <TInt> D[cnt+1];
  THash <TInt, TInt> deg;
  for(TUNGraph::TNodeI NI = G->BegNI(); NI < G->EndNI(); NI++) { 
    TInt tmp = NI.GetOutDeg() - G->IsEdge(NI.GetId(), NI.GetId() );
    D[tmp.Val].AddKey(NI.GetId());
    deg.AddDat(NI.GetId()) = tmp;
  }
  int max_k = 0;
  for(int num_iters = 0;num_iters < G->GetNodes(); num_iters++)
    for(int i = 0; i < cnt; i++)
      if(D[i].Empty() == 0) {
        max_k = max(max_k, i);
        TInt a = *(D[i].BegI());
        D[i].DelKey(a);
        deg.AddDat(a.Val) = -1; // Hope overwriting works
        TUNGraph::TNodeI NI = G->GetNI(a.Val);
        for(int e = 0; e < NI.GetOutDeg(); e++) {
          TInt b = NI.GetOutNId(e);
          if(deg.GetDat(b) >= 0) {
            int Id = deg.GetKeyId(b); 
            D[deg[Id].Val].DelKey(b);
            deg[Id] = deg[Id] - 1;  //Hope the overwriting works
            D[deg[Id]].AddKey(b);
          }
        }
        break;
      }
  return max_k;
}

void GetEigenVectorCentr(const PUNGraph& Graph, TIntFltH& EigenH, const double& Eps, const int& MaxIter) {
  const int NNodes = Graph->GetNodes();
  EigenH.Gen(NNodes);
  for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
    EigenH.AddDat(NI.GetId(), 1.0/NNodes);
    IAssert(NI.GetId() == EigenH.GetKey(EigenH.Len()-1));
  }
  TFltV TmpV(NNodes);
  double diff = TFlt::Mx;
  for (int iter = 0; iter < MaxIter; iter++) {
    int j = 0;
    for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++, j++) {
      TmpV[j] = 0;
      for (int e = 0; e < NI.GetOutDeg(); e++) {
        TmpV[j] += EigenH.GetDat(NI.GetOutNId(e)); }
    }
    double sum = 0;
    for (int i = 0; i < TmpV.Len(); i++) {
      EigenH[i] = TmpV[i];
      sum += EigenH[i];
    }
    for (int i = 0; i < EigenH.Len(); i++) {
      EigenH[i] /= sum; }
    if (fabs(diff-sum) < Eps) { break; }
    //printf("\tdiff:%f\tsum:%f\n", fabs(diff-sum), sum);
    diff = sum;
  }
}

int main(int argc, char* argv[]) {
  Env = TEnv(argc, argv, TNotify::StdNotify);
  Env.PrepArgs(TStr::Fmt("Node Centrality. build: %s, %s. Time: %s", __TIME__, __DATE__, TExeTm::GetCurTm()));
  TExeTm ExeTm;
  Try
  const TStr InFNm = Env.GetIfArgPrefixStr("-i:", "../as20graph.txt", "Input un/directed graph");
  const TStr OutFNm = Env.GetIfArgPrefixStr("-o:", "node_centrality.tab", "Output file");
  printf("Loading %s...", InFNm.CStr());
  PNGraph Graph = TSnap::LoadEdgeList<PNGraph>(InFNm);
  //PNGraph Graph = TSnap::GenRndGnm<PNGraph>(10, 10);
  //TGraphViz::Plot(Graph, gvlNeato, InFNm+".gif", InFNm, true);
  printf("nodes:%d  edges:%d\n", Graph->GetNodes(), Graph->GetEdges());
  PUNGraph UGraph = TSnap::ConvertGraph<PUNGraph>(Graph); // undirected version of the graph
  TIntFltH BtwH, EigH, PRankH, CcfH, CloseH, HubH, AuthH;
  //printf("Computing...\n");
  printf("Treat graph as DIRECTED: ");
  printf(" PageRank... ");             TSnap::GetPageRank(Graph, PRankH, 0.85);
  printf(" Hubs&Authorities...");      TSnap::GetHits(Graph, HubH, AuthH);
  printf("\nTreat graph as UNDIRECTED: ");
  printf(" Eigenvector...");           TSnap::GetEigenVectorCentr(UGraph, EigH);
  printf(" Clustering...");            TSnap::GetNodeClustCf(UGraph, CcfH);
  printf(" Betweenness (SLOW!)...");   TSnap::GetBetweennessCentr(UGraph, BtwH, 1.0);
  printf(" Constraint (SLOW!)...");    TNetConstraint<PUNGraph> NetC(UGraph, true);
  printf(" Closeness (SLOW!)...");
  for (TUNGraph::TNodeI NI = UGraph->BegNI(); NI < UGraph->EndNI(); NI++) {
    const int NId = NI.GetId();
    CloseH.AddDat(NId, TSnap::GetClosenessCentr<PUNGraph>(UGraph, NId, false));
  }
  printf("\nDONE! saving...");
  FILE *F = fopen(OutFNm.CStr(), "wt");
  fprintf(F,"#Network: %s\n", InFNm.CStr());
  fprintf(F,"#Nodes: %d\tEdges: %d\n", Graph->GetNodes(), Graph->GetEdges());
  fprintf(F,"#NodeId\tDegree\tCloseness\tBetweennes\tEigenVector\tNetworkConstraint\tClusteringCoefficient\tPageRank\tHubScore\tAuthorityScore\n");
  for (TUNGraph::TNodeI NI = UGraph->BegNI(); NI < UGraph->EndNI(); NI++) {
    const int NId = NI.GetId();
    const double DegCentr = UGraph->GetNI(NId).GetDeg();
    const double CloCentr = CloseH.GetDat(NId);
    const double BtwCentr = BtwH.GetDat(NId);
    const double EigCentr = EigH.GetDat(NId);
    const double Constraint = NetC.GetNodeC(NId);
    const double ClustCf = CcfH.GetDat(NId);
    const double PgrCentr = PRankH.GetDat(NId);
    const double HubCentr = HubH.GetDat(NId);
    const double AuthCentr = AuthH.GetDat(NId);
    fprintf(F, "%d\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\n", NId, 
      DegCentr, CloCentr, BtwCentr, EigCentr, Constraint, ClustCf, PgrCentr, HubCentr, AuthCentr);
  }
  fclose(F);
  Catch
  printf("\nrun time: %s (%s)\n", ExeTm.GetTmStr(), TSecTm::GetCurTm().GetTmStr().CStr());
  return 0;
}

double ave_path_length (PUNGraph p) {
  TVec<TInt> v;
  double tot_lengths = 0.0;
  for (TUNGraph::TNodeI n = p->BegNI(); n != p->EndNI(); n++) {
    v = v + n.GetId();
  }
  //  cerr << "vlen: " << v.Len() << endl;
  TBreathFS<PUNGraph> b(p);
  double tot_pairs = 0.0;
  while (v.Len () > 0) {
    TInt last = v[v.Len()-1];
    b.DoBfs (last, true, true);
    for (TVec<TInt>::TIter i = v.BegI(); (*i) != last; i++) {
      int length;
      length = b.GetHops (last, (*i));
      if (length == length) {
	tot_lengths += length;
	tot_pairs += 1;
      }
    }
    //    cerr << "tps: " << tot_pairs << ", last: " << last << ", beg: " << v[*(v.BegI())] << endl;
    v.Del(v.Len()-1);
  } 
  // cerr << "paths: " << tot_lengths << " " << tot_pairs << " " << (tot_lengths/tot_pairs) << endl;
  return tot_lengths / tot_pairs;
}

double GetGroupFarnessCentr(const PUNGraph& Graph, const TIntH& GroupNodes) {
  TIntH* NDistH = new TIntH[GroupNodes.Len()];

  for (int i = 0; i<GroupNodes.Len(); i++){
    NDistH[i](Graph->GetNodes());
    TSnap::GetShortPath<PUNGraph>(Graph, GroupNodes.GetDat(i), NDistH[i], true, TInt::Mx);
  }

  int min, dist, sum = 0, len = 0;
  for (PUNGraph::TObj::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++){
    if (NDistH[0].IsKey(NI.GetId()))
      min = NDistH[0].GetDat(NI.GetId());
    else
      min = -1;
    for (int j = 1; j<GroupNodes.Len(); j++){
      if (NDistH[j].IsKey(NI.GetId()))
        dist = NDistH[j].GetDat(NI.GetId());
      else
        dist = -1;
      if ((dist < min && dist != -1) || (dist > min && min == -1))
        min = dist;
    }
    if (min>0){
      sum += min;
      len++;
    }

  }

  if (len > 0) { return sum / double(len); }
  else { return 0.0; }
}

void GetEigenVectorCentr(const PUNGraph& Graph, TIntFltH& NIdEigenH, const double& Eps, const int& MaxIter) {
  const int NNodes = Graph->GetNodes();
  NIdEigenH.Gen(NNodes);
  // initialize vector values
  for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
    NIdEigenH.AddDat(NI.GetId(), 1.0 / NNodes);
    IAssert(NI.GetId() == NIdEigenH.GetKey(NIdEigenH.Len() - 1));
  }
  TFltV TmpV(NNodes);
  for (int iter = 0; iter < MaxIter; iter++) {
    int j = 0;
    // add neighbor values
    for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++, j++) {
      TmpV[j] = 0;
      for (int e = 0; e < NI.GetOutDeg(); e++) {
        TmpV[j] += NIdEigenH.GetDat(NI.GetOutNId(e));
      }
    }

    // normalize
    double sum = 0;
    for (int i = 0; i < TmpV.Len(); i++) {
      sum += (TmpV[i] * TmpV[i]);
    }
    sum = sqrt(sum);
    for (int i = 0; i < TmpV.Len(); i++) {
      TmpV[i] /= sum;
    }

    // compute difference
    double diff = 0.0;
    j = 0;
    for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++, j++) {
      diff += fabs(NIdEigenH.GetDat(NI.GetId()) - TmpV[j]);
    }

    // set new values
    j = 0;
    for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++, j++) {
      NIdEigenH.AddDat(NI.GetId(), TmpV[j]);
    }

    if (diff < Eps) {
      break;
    }
  }
}

double GetDegreeCentralization(const PUNGraph& Graph) {
  int MaxDeg = -1;
  int N = Graph->GetNodes();
  int Sum = 0;
  if (Graph->GetNodes() > 1 && (double(N - 2.0)*double(N - 1)) > 0) {
    for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
      int deg = NI.GetDeg();
      if (deg > MaxDeg) {
        MaxDeg = deg;
      }
    }
    for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
      Sum += MaxDeg - NI.GetDeg();
    }
    return double(Sum) / (double(N - 2.0)*double(N - 1));
  }
  else { return 0.0; }
}

double GetGroupDegreeCentr(const PUNGraph& Graph, const PUNGraph& Group) {
  int deg;
  TIntH NN;
  for (TUNGraph::TNodeI NI = Group->BegNI(); NI < Group->EndNI(); NI++) {
    deg = Graph->GetNI(NI.GetId()).GetDeg();
    for (int i = 0; i<deg; i++) {
      if (Group->IsNode(Graph->GetNI(NI.GetId()).GetNbrNId(i)) == 0)
        NN.AddDat(Graph->GetNI(NI.GetId()).GetNbrNId(i), NI.GetId());
    }
  }
  return (double)NN.Len();
}

 static double CmtyCMN(const PUNGraph& Graph, TCnComV& CmtyV) {
   TCNMQMatrix QMatrix(Graph);
   // maximize modularity
   while (QMatrix.MergeBestQ()) { }
   // reconstruct communities
   THash<TInt, TIntV> IdCmtyH;
   for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
     IdCmtyH.AddDat(QMatrix.CmtyIdUF.Find(NI.GetId())).Add(NI.GetId());
   }
   CmtyV.Gen(IdCmtyH.Len());
   for (int j = 0; j < IdCmtyH.Len(); j++) {
     CmtyV[j].NIdV.Swap(IdCmtyH[j]);
   }
   return QMatrix.Q;
 }

double GetAsstyCor(const PUNGraph& Graph) {
  TIntFltH deg(Graph->GetNodes()), deg_sq(Graph->GetNodes());
  for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
    deg.AddDat(NI.GetId()) = NI.GetOutDeg(); 
    deg_sq.AddDat(NI.GetId()) = NI.GetOutDeg() * NI.GetOutDeg();
  }
  double m = Graph->GetEdges(), num1 = 0.0, num2 = 0.0, den1 = 0.0;
  for (TUNGraph::TEdgeI EI = Graph->BegEI(); EI < Graph->EndEI(); EI++) {
    double t1 = deg.GetDat(EI.GetSrcNId()).Val, t2 = deg.GetDat(EI.GetDstNId()).Val;
    num1 += t1 * t2;
    num2 += t1 + t2;
    den1 += deg_sq.GetDat(EI.GetSrcNId()).Val + deg_sq.GetDat(EI.GetDstNId()).Val;
  }
  num1 /= m;
  den1 /= (2.0 * m);
  num2 = (num2 / (2.0 * m)) * (num2 / (2.0 * m));
  return (num1 - num2) / (den1 - num2);
}

/// Rewire the network. Keeps node degrees as is but randomly rewires the edges.
/// Use this function to generate a random graph with the same degree sequence 
/// as the OrigGraph. 
/// See:  On the uniform generation of random graphs with prescribed degree
/// sequences by R. Milo, N. Kashtan, S. Itzkovitz, M. E. J. Newman, U. Alon
/// URL: http://arxiv.org/abs/cond-mat/0312028
PUNGraph GenRewire(const PUNGraph& OrigGraph, const int& NSwitch, TRnd& Rnd) {
  const int Nodes = OrigGraph->GetNodes();
  const int Edges = OrigGraph->GetEdges();
  PUNGraph GraphPt = TUNGraph::New();
  TUNGraph& Graph = *GraphPt;
  Graph.Reserve(Nodes, -1);
  TExeTm ExeTm;
  // generate a graph that satisfies the constraints
  printf("Randomizing edges (%d, %d)...\n", Nodes, Edges);
  TIntPrSet EdgeSet(Edges);
  for (TUNGraph::TNodeI NI = OrigGraph->BegNI(); NI < OrigGraph->EndNI(); NI++) {
    const int NId = NI.GetId();
    for (int e = 0; e < NI.GetOutDeg(); e++) {
      if (NId <= NI.GetOutNId(e)) { continue; }
      EdgeSet.AddKey(TIntPr(NId, NI.GetOutNId(e)));
    }
    Graph.AddNode(NI.GetId());
  }
  // edge switching
  uint skip=0;
  for (uint swps = 0; swps < 2*uint(Edges)*uint(NSwitch); swps++) {
    const int keyId1 = EdgeSet.GetRndKeyId(Rnd);
    const int keyId2 = EdgeSet.GetRndKeyId(Rnd);
    if (keyId1 == keyId2) { skip++; continue; }
    const TIntPr& E1 = EdgeSet[keyId1];
    const TIntPr& E2 = EdgeSet[keyId2];
    TIntPr NewE1(E1.Val1, E2.Val1), NewE2(E1.Val2, E2.Val2);
    if (NewE1.Val1 > NewE1.Val2) { Swap(NewE1.Val1, NewE1.Val2); }
    if (NewE2.Val1 > NewE2.Val2) { Swap(NewE2.Val1, NewE2.Val2); }
    if (NewE1!=NewE2 && NewE1.Val1!=NewE1.Val2 && NewE2.Val1!=NewE2.Val2 && ! EdgeSet.IsKey(NewE1) && ! EdgeSet.IsKey(NewE2)) {
      EdgeSet.DelKeyId(keyId1);  EdgeSet.DelKeyId(keyId2);
      EdgeSet.AddKey(TIntPr(NewE1));
      EdgeSet.AddKey(TIntPr(NewE2));
    } else { skip++; }
    if (swps % Edges == 0) {
      printf("\r  %uk/%uk: %uk skip [%s]", swps/1000u, 2*uint(Edges)*uint(NSwitch)/1000u, skip/1000u, ExeTm.GetStr());
      if (ExeTm.GetSecs() > 2*3600) { printf(" *** Time limit!\n"); break; } // time limit 2 hours
    }
  }
  printf("\r  total %uk switchings attempted, %uk skiped  [%s]\n", 2*uint(Edges)*uint(NSwitch)/1000u, skip/1000u, ExeTm.GetStr());
  for (int e = 0; e < EdgeSet.Len(); e++) {
    Graph.AddEdge(EdgeSet[e].Val1, EdgeSet[e].Val2); }
  return GraphPt;
}

 void Init(const PUNGraph& Graph) {
   const double M = 0.5/Graph->GetEdges(); // 1/2m
   Q = 0.0;
   for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
     CmtyIdUF.Add(NI.GetId());
     const int OutDeg = NI.GetOutDeg();
     if (OutDeg == 0) { continue; }
     TCmtyDat& Dat = CmtyQH.AddDat(NI.GetId(), TCmtyDat(M * OutDeg, OutDeg));
     for (int e = 0; e < NI.GetOutDeg(); e++) {
       const int DstNId = NI.GetOutNId(e);
       const double DstMod = 2 * M * (1.0 - OutDeg * Graph->GetNI(DstNId).GetOutDeg() * M);
       Dat.AddQ(DstNId, DstMod);
     }
     Q += -1.0*TMath::Sqr(OutDeg*M);
     if (NI.GetId() < Dat.GetMxQNId()) {
       MxQHeap.Add(TFltIntIntTr(Dat.GetMxQ(), NI.GetId(), Dat.GetMxQNId())); }
   }
   MxQHeap.MakeHeap();
 }

int FastCorePeriphery(PUNGraph& Graph, TIntIntH& out) {

    TIntIntH nodes;
    double Z=0;

    for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) { // Calculate and store the degrees of each node.
        int deg = NI.GetDeg();
        int id = NI.GetId();
        Z += deg;
        nodes.AddDat(id,deg);
    }

    Z = Z/2;

    nodes.SortByDat(false); // Then sort the nodes in descending order of degree, to get a list of nodes {v1, v2, . . . , vn}.

    double Zbest = 99999900000000000;
    int kbest = 0;

    int br=0;
    for (int k=0; k<nodes.Len(); k++) {
        br++;
        Z = Z + br - 1 - nodes[k];
        if (Z < Zbest) { // or <=
            Zbest = Z;
            kbest = br;
        }
    }

    int cp = 0;
    br = 0;
    for (THashKeyDatI<TInt, TInt> it = nodes.BegI();  !it.IsEnd(); it++) {
        if (br < kbest)
            cp = 1;
        else
            cp = 0;
        out.AddDat(it.GetKey(), cp);
        br++;
    }

    return kbest;
}

// Maximum modularity clustering by Girvan-Newman algorithm (slow)
//  Girvan M. and Newman M. E. J., Community structure in social and biological networks, Proc. Natl. Acad. Sci. USA 99, 7821–7826 (2002)
double CommunityGirvanNewman(PUNGraph& Graph, TCnComV& CmtyV) {
  TIntH OutDegH;
  const int NEdges = Graph->GetEdges();
  for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
    OutDegH.AddDat(NI.GetId(), NI.GetOutDeg());
  }
  double BestQ = -1; // modularity
  TCnComV CurCmtyV;
  CmtyV.Clr();
  TIntV Cmty1, Cmty2;
  while (true) {
    CmtyGirvanNewmanStep(Graph, Cmty1, Cmty2);
    const double Q = _GirvanNewmanGetModularity(Graph, OutDegH, NEdges, CurCmtyV);
    //printf("current modularity: %f\n", Q);
    if (Q > BestQ) {
      BestQ = Q;
      CmtyV.Swap(CurCmtyV);
    }
    if (Cmty1.Len()==0 || Cmty2.Len() == 0) { break; }
  }
  return BestQ;
}

// Maximum Domination Problem
void MaxCPGreedyBetter(const PUNGraph& Graph, const int k, TIntH& GroupNodes) {
  // buildup cpntainer of group nodes
  const int n = Graph->GetNodes();
  int *NNodes = new int[n]; // container of neighbouring nodes
  int NNodes_br = 0;
  TIntH Nodes; // nodes sorted by vd
  double gc = 0, gc0 = 0;
  int addId = 0, addIdPrev = 0;

  for (TUNGraph::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++){
    Nodes.AddDat(NI.GetId(), NI.GetDeg());
  }

  Nodes.SortByDat(false);

  int br = 0;
  while (br < k) {
    for (THashKeyDatI<TInt, TInt> NI = Nodes.BegI(); NI < Nodes.EndI(); NI++){
      if ((NI.GetDat() <= (int)gc0))
        break;
      gc = NI.GetDat() - Intersect(Graph->GetNI(NI.GetKey()), NNodes, NNodes_br);
      if (gc>gc0){
        gc0 = gc;
        addId = NI.GetKey();
      }
    }

    if (addId != addIdPrev) {

      GroupNodes.AddDat(br, addId);
      br++;
      gc0 = 0;

      int nn = addId;
      bool nnnew = true;
      for (int j = 0; j<NNodes_br; j++)
        if (NNodes[j] == nn){
        nnnew = false;
        j = NNodes_br;
        }

      if (nnnew){
        NNodes[NNodes_br] = nn;
        NNodes_br++;
      }

      for (int i = 0; i<Graph->GetNI(addId).GetDeg(); i++) {
        int nn = Graph->GetNI(addId).GetNbrNId(i);
        bool nnnew = true;
        for (int j = 0; j<NNodes_br; j++) {
          if (NNodes[j] == nn){
            nnnew = false;
            j = NNodes_br;
          }
        }
        if (nnnew){
          NNodes[NNodes_br] = nn;
          NNodes_br++;
        }
      }
      addIdPrev = addId;
      Nodes.DelKey(addId);
    }
    else {
      br = k;
    }
    printf("%i,", br);
  }

  delete NNodes;
}