/// Removes any gaps in node labels. ##TPRManager::CheckGap
void CheckGap (int GapLabel) {
for (TNEANet::TNodeI NI = Net->BegNI(); NI != Net->EndNI(); NI++) {
int NId = NI.GetId();
int OldLabel = LabelsV[NId];
if (OldLabel > GapLabel && OldLabel <= LabelLimit) {
LabelsV[NId] = MaxLabel;
LabelCounts[OldLabel]--;
LabelCounts[MaxLabel]++;
if (IsActive(NId)) { RemoveActive(NId); }
}
}
LabelLimit = GapLabel - 1;
}
TPRManager(PNEANet &Net) : Net(Net), CapIndex(0), FlowV(Net->GetMxEId()), ExcessV(Net->GetMxNId()), EdgeNumsV(Net->GetMxNId()), LabelsV(Net->GetMxNId()), LabelCounts(Net->GetNodes() + 1), LabelLimit(0), MaxLabel(Net->GetNodes()), ActiveNodeSet(Net->GetMxNId()), ActiveCount(0) {
CapIndex = Net->GetIntAttrIndE(CapAttrName);
for (int i = 0; i <= Net->GetNodes(); i++) { LabelCounts[i] = 0; }
for (TNEANet::TEdgeI EI = Net->BegEI(); EI != Net->EndEI(); EI++) {
int EId = EI.GetId();
IAssert(Capacity(EId) >= 0);
FlowV[EId] = 0;
}
for (TNEANet::TNodeI NI = Net->BegNI(); NI != Net->EndNI(); NI++) {
int NId = NI.GetId();
ExcessV[NId] = 0;
EdgeNumsV[NId] = 0;
ActiveNodeSet[NId] = 0;
}
LabelCounts[0] = Net->GetNodes();
}
/// Implements the Global Relabeling heuristic. ##TSnap::GlobalRelabel
void GlobalRelabel (PNEANet &Net, TPRManager &PRM, const int& SrcNId, const int& SnkNId) {
TIntQ NodeQ;
int size = Net->GetMxNId();
TIntV NodeV(size);
for (int i = 0; i < size; i++) { NodeV[i] = 0; }
NodeQ.Push(SnkNId);
NodeV[SnkNId] = 1;
int MaxLabel = PRM.GetMaxLabel();
while (!NodeQ.Empty()) {
// Backward search
int NId = NodeQ.Top(); NodeQ.Pop();
const TNEANet::TNodeI &NI = Net->GetNI(NId);
// Check all edges that point out of the current node for those over which flow can be returned.
for (int EdgeN = 0; EdgeN < NI.GetOutDeg(); EdgeN++) {
int OutNId = NI.GetOutNId(EdgeN);
int EId = NI.GetOutEId(EdgeN);
if (!NodeV[OutNId] && PRM.Flow(EId) > 0) {
NodeV[OutNId] = 1;
NodeQ.Push(OutNId);
PRM.SetLabel(OutNId, PRM.Label(NId) + 1);
}
}
// Check all edges that point into the current node for those over which flow can be added.
for (int EdgeN = 0; EdgeN < NI.GetInDeg(); EdgeN++) {
int InNId = NI.GetInNId(EdgeN);
int EId = NI.GetInEId(EdgeN);
if (!NodeV[InNId] && PRM.Capacity(EId) > PRM.Flow(EId)) {
NodeV[InNId] = 1;
NodeQ.Push(InNId);
PRM.SetLabel(InNId, PRM.Label(NId) + 1);
}
}
}
for (TNEANet::TNodeI NI = Net->BegNI(); NI != Net->EndNI(); NI++) {
int NId = NI.GetId();
if (NodeV[NId]) {
if (PRM.Excess(NId) > 0 && PRM.Label(NId) < MaxLabel && NId != SnkNId) {
if (!PRM.IsActive(NId)) { PRM.PushActive(NId); }
}
} else {
if (PRM.IsActive(NId)) { PRM.RemoveActive(NId); }
PRM.SetLabel(NId, MaxLabel);
}
}
}
int GetMaxFlowIntPR (PNEANet &Net, const int& SrcNId, const int& SnkNId) {
IAssert(Net->IsNode(SrcNId));
IAssert(Net->IsNode(SnkNId));
if (SrcNId == SnkNId) { return 0; }
TPRManager PRM(Net);
int MaxLabel = PRM.GetMaxLabel();
TNEANet::TNodeI SrcNI = Net->GetNI(SrcNId);
for (int EdgeN = 0; EdgeN < SrcNI.GetOutDeg(); EdgeN++) {
int EId = SrcNI.GetOutEId(EdgeN);
int OutNId = SrcNI.GetOutNId(EdgeN);
if (OutNId != SrcNId) {
int Capacity = PRM.Capacity(EId);
PRM.Flow(EId) = Capacity;
PRM.Excess(OutNId) = Capacity;
}
}
GlobalRelabel(Net, PRM, SrcNId, SnkNId);
PRM.SetLabel(SrcNId, MaxLabel);
int RelabelCount = 1;
int GRRate = Net->GetNodes();
while (PRM.HasActive()) {
int NId = PRM.PopActive();
const TNEANet::TNodeI &NI = Net->GetNI(NId);
int PrevLabel = MaxLabel;
while (PRM.Excess(NId) > 0 && PRM.Label(NId) <= PrevLabel) {
PrevLabel = PRM.Label(NId);
int NbrNId = PushRelabel(PRM, NId, NI);
if (NbrNId != -1 && NbrNId != SnkNId && PRM.Excess(NbrNId) > 0 && !PRM.IsActive(NbrNId)) {
PRM.PushActive(NbrNId);
}
}
if (PRM.Excess(NId) > 0 && PRM.Label(NId) < MaxLabel) {
PRM.PushActive(NId);
}
if (RelabelCount % GRRate == 0) { GlobalRelabel(Net, PRM, SrcNId, SnkNId); }
}
return PRM.Excess(SnkNId);
}
/// Returns the ID of the neighbor that \c NId pushes to, -1 if no push was made.
int PushRelabel (TPRManager &PRM, const int &NId, const TNEANet::TNodeI &NI) {
int EdgeN = PRM.EdgeNum(NId);
int EId = -1, NbrNId = -1, ResFlow = 0;
int Cutoff = NI.GetInDeg();
if (EdgeN < Cutoff) {
EId = NI.GetInEId(EdgeN);
NbrNId = NI.GetInNId(EdgeN);
ResFlow = PRM.Flow(EId);
} else {
EId = NI.GetOutEId(EdgeN - Cutoff);
NbrNId = NI.GetOutNId(EdgeN - Cutoff);
ResFlow = PRM.Capacity(EId) - PRM.Flow(EId);
}
if (ResFlow > 0 && PRM.Label(NId) - 1 == PRM.Label(NbrNId)) {
if (EdgeN < Cutoff) {
PushToInNbr(PRM, NId, NbrNId, EId);
} else {
PushToOutNbr(PRM, NId, NbrNId, EId);
}
return NbrNId;
}
if (EdgeN + 1 == NI.GetDeg()) {
PRM.EdgeNum(NId) = 0;
Relabel(PRM, NId, NI);
} else {
PRM.EdgeNum(NId)++;
}
return -1;
}
int GetWeightedPageRankMP1(const PNEANet Graph, TIntFltH& PRankH, const TStr& Attr, const double& C, const double& Eps, const int& MaxIter) {
if (!Graph->IsFltAttrE(Attr)) return -1;
TFltV Weights = Graph->GetFltAttrVecE(Attr);
int mxid = Graph->GetMxNId();
TFltV OutWeights(mxid);
Graph->GetWeightOutEdgesV(OutWeights, Weights);
/*for (TNEANet::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
OutWeights[NI.GetId()] = Graph->GetWeightOutEdges(NI, Attr);
}*/
/*TIntFltH Weights;
for (TNEANet::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
Weights.AddDat(NI.GetId(), Graph->GetWeightOutEdges(NI, Attr));
}*/
const int NNodes = Graph->GetNodes();
TVec<TNEANet::TNodeI> NV;
//const double OneOver = 1.0/double(NNodes);
PRankH.Gen(NNodes);
for (TNEANet::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
NV.Add(NI);
PRankH.AddDat(NI.GetId(), 1.0/NNodes);
//IAssert(NI.GetId() == PRankH.GetKey(PRankH.Len()-1));
}
TFltV TmpV(NNodes);
for (int iter = 0; iter < MaxIter; iter++) {
#pragma omp parallel for schedule(dynamic,10000)
for (int j = 0; j < NNodes; j++) {
TNEANet::TNodeI NI = NV[j];
TmpV[j] = 0;
for (int e = 0; e < NI.GetInDeg(); e++) {
const int InNId = NI.GetInNId(e);
const TFlt OutWeight = OutWeights[InNId];
int EId = Graph->GetEId(InNId, NI.GetId());
const TFlt Weight = Weights[Graph->GetFltKeyIdE(EId)];
if (OutWeight > 0) {
TmpV[j] += PRankH.GetDat(InNId) * Weight / OutWeight; }
}
TmpV[j] = C*TmpV[j]; // Berkhin (the correct way of doing it)
//TmpV[j] = C*TmpV[j] + (1.0-C)*OneOver; // iGraph
}
double diff=0, sum=0, NewVal;
#pragma omp parallel for reduction(+:sum) schedule(dynamic,10000)
for (int i = 0; i < TmpV.Len(); i++) { sum += TmpV[i]; }
const double Leaked = (1.0-sum) / double(NNodes);
#pragma omp parallel for reduction(+:diff) schedule(dynamic,10000)
for (int i = 0; i < PRankH.Len(); i++) { // re-instert leaked PageRank
NewVal = TmpV[i] + Leaked; // Berkhin
//NewVal = TmpV[i] / sum; // iGraph
diff += fabs(NewVal-PRankH[i]);
PRankH[i] = NewVal;
}
if (diff < Eps) { break; }
}
return 0;
}
/// Increases the label of a node \c NId to allow valid pushes to some neighbor.
void Relabel (TPRManager &PRM, const int &NId, const TNEANet::TNodeI &NI) {
int MaxLabel = PRM.GetMaxLabel();
int MinLabel = MaxLabel;
for (int EdgeN = 0; EdgeN < NI.GetInDeg(); EdgeN++) {
if (PRM.Flow(NI.GetInEId(EdgeN)) > 0) {
int InLabel = PRM.Label(NI.GetInNId(EdgeN));
MinLabel = min(MinLabel, InLabel);
}
}
for (int EdgeN = 0; EdgeN < NI.GetOutDeg(); EdgeN++) {
if (PRM.Capacity(NI.GetOutEId(EdgeN)) > PRM.Flow(NI.GetOutEId(EdgeN))) {
int OutLabel = PRM.Label(NI.GetOutNId(EdgeN));
MinLabel = min(MinLabel, OutLabel);
}
}
if (MinLabel == MaxLabel) {
PRM.SetLabel(NId, MaxLabel);
} else {
PRM.SetLabel(NId, MinLabel + 1);
}
}
// Test node, edge creation
void ManipulateNodesEdges() {
int NNodes = 1000;
int NEdges = 100000;
const char *FName = "demo.graph.dat";
PNEANet Graph;
PNEANet Graph1;
PNEANet Graph2;
int i;
int n;
int NCount;
int ECount1;
int ECount2;
int x,y;
bool t;
Graph = TNEANet::New();
t = Graph->Empty();
// create the nodes
for (i = 0; i < NNodes; i++) {
Graph->AddNode(i);
}
n = Graph->GetNodes();
t = Graph->Empty();
// create random edges
NCount = NEdges;
while (NCount > 0) {
x = rand() % NNodes;
y = rand() % NNodes;
n = Graph->AddEdge(x, y);
NCount--;
}
PrintGStats("ManipulateNodesEdges:Graph",Graph);
// get all the nodes
NCount = 0;
for (TNEANet::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
NCount++;
}
// get all the edges for all the nodes
ECount1 = 0;
for (TNEANet::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
for (int e = 0; e < NI.GetOutDeg(); e++) {
ECount1++;
}
}
// get all the edges directly
ECount2 = 0;
for (TNEANet::TEdgeI EI = Graph->BegEI(); EI < Graph->EndEI(); EI++) {
ECount2++;
}
printf("graph ManipulateNodesEdges:Graph, nodes %d, edges1 %d, edges2 %d\n",
NCount, ECount1, ECount2);
// assignment
Graph1 = TNEANet::New();
*Graph1 = *Graph;
PrintGStats("ManipulateNodesEdges:Graph1",Graph1);
// save the graph
{
TFOut FOut(FName);
Graph->Save(FOut);
FOut.Flush();
}
// load the graph
{
TFIn FIn(FName);
Graph2 = TNEANet::Load(FIn);
}
PrintGStats("ManipulateNodesEdges:Graph2",Graph2);
// remove all the nodes and edges
for (i = 0; i < NNodes; i++) {
n = Graph->GetRndNId();
Graph->DelNode(n);
}
PrintGStats("ManipulateNodesEdges:Graph",Graph);
Graph1->Clr();
PrintGStats("ManipulateNodesEdges:Graph1",Graph1);
}
int GetWeightedPageRankMP2(const PNEANet Graph, TIntFltH& PRankH, const TStr& Attr, const double& C, const double& Eps, const int& MaxIter) {
if (!Graph->IsFltAttrE(Attr)) return -1;
const int NNodes = Graph->GetNodes();
TVec<TNEANet::TNodeI> NV;
//const double OneOver = 1.0/double(NNodes);
PRankH.Gen(NNodes);
int MxId;
for (TNEANet::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
NV.Add(NI);
PRankH.AddDat(NI.GetId(), 1.0/NNodes);
int Id = NI.GetId();
if (Id > MxId) {
MxId = Id;
}
}
TFltV PRankV(MxId+1);
TFltV OutWeights(MxId+1);
TFltV Weights = Graph->GetFltAttrVecE(Attr);
#pragma omp parallel for schedule(dynamic,10000)
for (int j = 0; j < NNodes; j++) {
TNEANet::TNodeI NI = NV[j];
int Id = NI.GetId();
OutWeights[Id] = Graph->GetWeightOutEdges(NI, Attr);
PRankV[Id] = 1/NNodes;
}
TFltV TmpV(NNodes);
for (int iter = 0; iter < MaxIter; iter++) {
#pragma omp parallel for schedule(dynamic,10000)
for (int j = 0; j < NNodes; j++) {
TNEANet::TNodeI NI = NV[j];
TFlt Tmp = 0;
for (int e = 0; e < NI.GetInDeg(); e++) {
const int InNId = NI.GetInNId(e);
const TFlt OutWeight = OutWeights[InNId];
int EId = Graph->GetEId(InNId, NI.GetId());
const TFlt Weight = Weights[Graph->GetFltKeyIdE(EId)];
if (OutWeight > 0) {
Tmp += PRankH.GetDat(InNId) * Weight / OutWeight;
}
}
TmpV[j] = C*Tmp; // Berkhin (the correct way of doing it)
//TmpV[j] = C*TmpV[j] + (1.0-C)*OneOver; // iGraph
}
double sum = 0;
#pragma omp parallel for reduction(+:sum) schedule(dynamic,10000)
for (int i = 0; i < TmpV.Len(); i++) { sum += TmpV[i]; }
const double Leaked = (1.0-sum) / double(NNodes);
double diff = 0;
#pragma omp parallel for reduction(+:diff) schedule(dynamic,10000)
for (int i = 0; i < NNodes; i++) {
TNEANet::TNodeI NI = NV[i];
double NewVal = TmpV[i] + Leaked; // Berkhin
//NewVal = TmpV[i] / sum; // iGraph
int Id = NI.GetId();
diff += fabs(NewVal-PRankV[Id]);
PRankV[Id] = NewVal;
}
if (diff < Eps) { break; }
}
#pragma omp parallel for schedule(dynamic,10000)
for (int i = 0; i < NNodes; i++) {
TNEANet::TNodeI NI = NV[i];
PRankH[i] = PRankV[NI.GetId()];
}
return 0;
}
// Test node, edge creation
TEST(TNEANet, ManipulateNodesEdges) {
int NNodes = 1000;
int NEdges = 100000;
const char *FName = "test.graph.dat";
PNEANet Graph;
PNEANet Graph1;
PNEANet Graph2;
int i;
int n;
int NCount;
int x,y;
int Deg, InDeg, OutDeg;
Graph = TNEANet::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);
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 (TNEANet::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
NCount++;
}
EXPECT_EQ(NNodes,NCount);
// edges per node iterator
NCount = 0;
for (TNEANet::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 (TNEANet::TEdgeI EI = Graph->BegEI(); EI < Graph->EndEI(); EI++) {
NCount++;
}
EXPECT_EQ(NEdges,NCount);
// node degree
for (TNEANet::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
Deg = NI.GetDeg();
InDeg = NI.GetInDeg();
OutDeg = NI.GetOutDeg();
EXPECT_EQ(Deg,InDeg+OutDeg);
}
// assignment
Graph1 = TNEANet::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();
}
{
TFIn FIn(FName);
Graph2 = TNEANet::Load(FIn);
}
EXPECT_EQ(NNodes,Graph2->GetNodes());
EXPECT_EQ(NEdges,Graph2->GetEdges());
EXPECT_EQ(0,Graph2->Empty());
EXPECT_EQ(1,Graph2->IsOk());
// remove all the nodes and edges
for (i = 0; i < NNodes; i++) {
n = Graph->GetRndNId();
Graph->DelNode(n);
}
EXPECT_EQ(0,Graph->GetNodes());
EXPECT_EQ(0,Graph->GetEdges());
EXPECT_EQ(1,Graph->IsOk());
EXPECT_EQ(1,Graph->Empty());
Graph1->Clr();
EXPECT_EQ(0,Graph1->GetNodes());
EXPECT_EQ(0,Graph1->GetEdges());
EXPECT_EQ(1,Graph1->IsOk());
EXPECT_EQ(1,Graph1->Empty());
}