TUNGraph Class Reference

Undirected graph. More...

#include <graph.h>

Classes
class	TEdgeI
	Edge iterator. Only forward iteration (operator++) is supported. More...
class	TLoadTNodeInitializer
class	TNode
class	TNodeI
	Node iterator. Only forward iteration (operator++) is supported. More...

Public Types
typedef TUNGraph	TNet
typedef TPt< TUNGraph >	PNet

Public Member Functions
	TUNGraph ()
	TUNGraph (const int &Nodes, const int &Edges)
	Constructor that reserves enough memory for a graph of Nodes nodes and Edges edges. More...
	TUNGraph (const TUNGraph &Graph)
	TUNGraph (TSIn &SIn)
	Constructor that loads the graph from a (binary) stream SIn. More...
void	Save (TSOut &SOut) const
	Saves the graph to a (binary) stream SOut. More...
bool	HasFlag (const TGraphFlag &Flag) const
	Allows for run-time checking the type of the graph (see the TGraphFlag for flags). More...
TUNGraph &	operator= (const TUNGraph &Graph)
int	GetNodes () const
	Returns the number of nodes in the graph. More...
int	AddNode (int NId=-1)
	Adds a node of ID NId to the graph. More...
int	AddNodeUnchecked (int NId=-1)
	Adds a node of ID NId to the network, noop if the node already exists. More...
int	AddNode (const TNodeI &NodeI)
	Adds a node of ID NodeI.GetId() to the graph. More...
int	AddNode (const int &NId, const TIntV &NbrNIdV)
	Adds a node of ID NId to the graph and create edges to all nodes in vector NbrNIdV. More...
int	AddNode (const int &NId, const TVecPool< TInt > &Pool, const int &NIdVId)
	Adds a node of ID NId to the graph and create edges to all nodes in vector NIdVId in the vector pool Pool. More...
void	DelNode (const int &NId)
	Deletes node of ID NId from the graph. More...
void	DelNode (const TNode &NodeI)
	Deletes node of ID NodeI.GetId() from the graph. More...
bool	IsNode (const int &NId) const
	Tests whether ID NId is a node. More...
TNodeI	BegNI () const
	Returns an iterator referring to the first node in the graph. More...
TNodeI	EndNI () const
	Returns an iterator referring to the past-the-end node in the graph. More...
TNodeI	GetNI (const int &NId) const
	Returns an iterator referring to the node of ID NId in the graph. More...
int	GetMxNId () const
	Returns an ID that is larger than any node ID in the graph. More...
int	GetEdges () const
	Returns the number of edges in the graph. More...
int	AddEdge (const int &SrcNId, const int &DstNId)
	Adds an edge between node IDs SrcNId and DstNId to the graph. More...
int	AddEdgeUnchecked (const int &SrcNId, const int &DstNId)
	Adds an edge between node IDs SrcNId and DstNId to the graph. More...
int	AddEdge2 (const int &SrcNId, const int &DstNId)
	Adds an edge between node IDs SrcNId and DstNId to the graph. If nodes do not exists, create them. More...
int	AddEdge (const TEdgeI &EdgeI)
	Adds an edge between EdgeI.GetSrcNId() and EdgeI.GetDstNId() to the graph. More...
void	DelEdge (const int &SrcNId, const int &DstNId)
	Deletes an edge between node IDs SrcNId and DstNId from the graph. More...
bool	IsEdge (const int &SrcNId, const int &DstNId) const
	Tests whether an edge between node IDs SrcNId and DstNId exists in the graph. More...
TEdgeI	BegEI () const
	Returns an iterator referring to the first edge in the graph. More...
TEdgeI	EndEI () const
	Returns an iterator referring to the past-the-end edge in the graph. More...
TEdgeI	GetEI (const int &EId) const
	Not supported/implemented! More...
TEdgeI	GetEI (const int &SrcNId, const int &DstNId) const
	Returns an iterator referring to edge (SrcNId, DstNId) in the graph. More...
int	GetRndNId (TRnd &Rnd=TInt::Rnd)
	Returns an ID of a random node in the graph. More...
TNodeI	GetRndNI (TRnd &Rnd=TInt::Rnd)
	Returns an interator referring to a random node in the graph. More...
void	GetNIdV (TIntV &NIdV) const
	Gets a vector IDs of all nodes in the graph. More...
bool	Empty () const
	Tests whether the graph is empty (has zero nodes). More...
void	Clr ()
	Deletes all nodes and edges from the graph. More...
void	SortNodeAdjV ()
	Sorts the adjacency lists of each node. More...
void	Reserve (const int &Nodes, const int &Edges)
	Reserves memory for a graph of Nodes nodes and Edges edges. More...
void	ReserveNIdDeg (const int &NId, const int &Deg)
	Reserves memory for node ID NId having Deg edges. More...
void	Defrag (const bool &OnlyNodeLinks=false)
	Defragments the graph. More...
bool	IsOk (const bool &ThrowExcept=true) const
	Checks the graph data structure for internal consistency. More...
void	Dump (FILE *OutF=stdout) const
	Print the graph in a human readable form to an output stream OutF. More...

Static Public Member Functions
static PUNGraph	New ()
	Static constructor that returns a pointer to the graph. Call: PUNGraph Graph = TUNGraph::New(). More...
static PUNGraph	New (const int &Nodes, const int &Edges)
	Static constructor that returns a pointer to the graph and reserves enough memory for Nodes nodes and Edges edges. More...
static PUNGraph	Load (TSIn &SIn)
	Static constructor that loads the graph from a stream SIn and returns a pointer to it. More...
static PUNGraph	LoadShM (TShMIn &ShMIn)
	Static constructor that loads the graph from shared memory. More...
static PUNGraph	GetSmallGraph ()
	Returns a small graph on 5 nodes and 5 edges. More...

Private Member Functions
TNode &	GetNode (const int &NId)
const TNode &	GetNode (const int &NId) const
void	LoadGraphShM (TShMIn &ShMIn)

Private Attributes
TCRef	CRef
TInt	MxNId
TInt	NEdges
THash< TInt, TNode >	NodeH

Friends
class	TUNGraphMtx
class	TPt< TUNGraph >

Detailed Description

Undirected graph.

Node IDs can be arbitrary non-negative integers. Nodes and edges have no attributes/data associated with them. There is at most one undirected edge between a pair of nodes. Self loops (one per node) are allowed but multiple (parallel) edges are not. The undirected graph data structure is implemented using sorted adjacency lists. This means adding a node takes constant time, while adding an edge takes linear time (since adjacency list is kept sorted) in the node degree. Accessing arbitrary node takes constant time and accessing any edge takes logarithmic time in the node degree.

Definition at line 32 of file graph.h.

Member Typedef Documentation

typedef TPt<TUNGraph> TUNGraph::PNet

Definition at line 35 of file graph.h.

typedef TUNGraph TUNGraph::TNet

Definition at line 34 of file graph.h.

Constructor & Destructor Documentation

TUNGraph::TUNGraph ( )

inline

Definition at line 162 of file graph.h.

: CRef(), MxNId(0), NEdges(0), NodeH() { }

TUNGraph::TUNGraph ( const int &  Nodes, const int &  Edges  )

inlineexplicit

Constructor that reserves enough memory for a graph of Nodes nodes and Edges edges.

Definition at line 164 of file graph.h.

: MxNId(0), NEdges(0) { Reserve(Nodes, Edges); }

TUNGraph::TUNGraph ( const TUNGraph &  Graph )

inline

Definition at line 165 of file graph.h.

: MxNId(Graph.MxNId), NEdges(Graph.NEdges), NodeH(Graph.NodeH) { }

TUNGraph::TUNGraph ( TSIn &  SIn )

inline

Constructor that loads the graph from a (binary) stream SIn.

Definition at line 167 of file graph.h.

: MxNId(SIn), NEdges(SIn), NodeH(SIn) { }

Member Function Documentation

int TUNGraph::AddEdge	(	const int &	SrcNId,
		const int &	DstNId
	)

Adds an edge between node IDs SrcNId and DstNId to the graph.

If the edge already exists return -2. If the edge was successfully added return -1. Normally the function should return an ID of the edge added but since edges in TUNGraph have no IDs we return -1. The function aborts if SrcNId or DstNId are not nodes in the graph.

Definition at line 92 of file graph.cpp.

                                                          {
  IAssertR(IsNode(SrcNId) && IsNode(DstNId), TStr::Fmt("%d or %d not a node.", SrcNId, DstNId).CStr());
  if (IsEdge(SrcNId, DstNId)) { return -2; } // edge already exists
  GetNode(SrcNId).NIdV.AddSorted(DstNId);
  if (SrcNId!=DstNId) { // not a self edge
    GetNode(DstNId).NIdV.AddSorted(SrcNId); }
  NEdges++;
  return -1; // no edge id
}

int TUNGraph::AddEdge ( const TEdgeI &  EdgeI )

inline

Adds an edge between EdgeI.GetSrcNId() and EdgeI.GetDstNId() to the graph.

Definition at line 265 of file graph.h.

{ return AddEdge(EdgeI.GetSrcNId(), EdgeI.GetDstNId()); }

int TUNGraph::AddEdge2	(	const int &	SrcNId,
		const int &	DstNId
	)

Adds an edge between node IDs SrcNId and DstNId to the graph. If nodes do not exists, create them.

Definition at line 112 of file graph.cpp.

                                                           {
  if (! IsNode(SrcNId)) { AddNode(SrcNId); }
  if (! IsNode(DstNId)) { AddNode(DstNId); }
  if (GetNode(SrcNId).IsNbrNId(DstNId)) { return -2; } // edge already exists
  GetNode(SrcNId).NIdV.AddSorted(DstNId);
  if (SrcNId!=DstNId) { // not a self edge
    GetNode(DstNId).NIdV.AddSorted(SrcNId); }
  NEdges++;
  return -1; // no edge id
}

int TUNGraph::AddEdgeUnchecked	(	const int &	SrcNId,
		const int &	DstNId
	)

Adds an edge between node IDs SrcNId and DstNId to the graph.

Returns -1. The method assumes that SrcNId and DstNId are existing nodes in the graph and adds new neighbor values at the end of their adjacency vectors. No checks are performed to verify these assumptions. Adjacency vectors must be sorted and have duplicates removed after a sequence of these operations to assure consistency of data structures.

Definition at line 103 of file graph.cpp.

                                                                   {
  GetNode(SrcNId).NIdV.Add(DstNId);
  if (SrcNId!=DstNId) { // not a self edge
    GetNode(DstNId).NIdV.Add(SrcNId); }
  NEdges++;
  return -1; // no edge id
}

int TUNGraph::AddNode

(

int

NId = -1

)

Adds a node of ID NId to the graph.

Returns the ID of the node being added. If NId is -1, node ID is automatically assigned. Aborts, if a node with ID NId already exists.

Definition at line 8 of file graph.cpp.

                             {
  if (NId == -1) {
    NId = MxNId;  MxNId++;
  } else {
    IAssertR(!IsNode(NId), TStr::Fmt("NodeId %d already exists", NId));
    MxNId = TMath::Mx(NId+1, MxNId());
  }
  NodeH.AddDat(NId, TNode(NId));
  return NId;
}

int TUNGraph::AddNode ( const TNodeI &  NodeI )

inline

Adds a node of ID NodeI.GetId() to the graph.

Definition at line 206 of file graph.h.

{ return AddNode(NodeI.GetId()); }

int TUNGraph::AddNode	(	const int &	NId,
		const TIntV &	NbrNIdV
	)

Adds a node of ID NId to the graph and create edges to all nodes in vector NbrNIdV.

Returns the ID of the node being added. If NId is -1, node ID is automatically assigned. Aborts, if a node with ID NId already exists.

The operation can create inconsistent graphs when the neighboring nodes in NbrNIdV vector do not exist. Use TUNGraph::IsOk to check that the resulting graph is consistent after the operation.

Definition at line 28 of file graph.cpp.

                                                          {
  int NewNId;
  if (NId == -1) {
    NewNId = MxNId;  MxNId++;
  } else {
    IAssertR(! IsNode(NId), TStr::Fmt("NodeId %d already exists", NId));
    NewNId = NId;
    MxNId = TMath::Mx(NewNId+1, MxNId());
  }
  TNode& Node = NodeH.AddDat(NewNId);
  Node.Id = NewNId;
  Node.NIdV = NbrNIdV;
  Node.NIdV.Sort();
  NEdges += Node.GetDeg();
  for (int i = 0; i < NbrNIdV.Len(); i++) {
    GetNode(NbrNIdV[i]).NIdV.AddSorted(NewNId);
  }
  return NewNId;
}

int TUNGraph::AddNode	(	const int &	NId,
		const TVecPool< TInt > &	Pool,
		const int &	NIdVId
	)

Adds a node of ID NId to the graph and create edges to all nodes in vector NIdVId in the vector pool Pool.

Returns the ID of the node being added. If NId is -1, node ID is automatically assigned. Aborts, if a node with ID NId already exists.

The operation can create inconsistent graphs when the neighboring nodes stored in the Pool vector are not explicitly added to the graph. Use TUNGraph::IsOk to check that the resulting graph is consistent.

Definition at line 49 of file graph.cpp.

                                                                                   {
  int NewNId;
  if (NId == -1) {
    NewNId = MxNId;  MxNId++;
  } else {
    IAssertR(!IsNode(NId), TStr::Fmt("NodeId %d already exists", NId));
    NewNId = NId;
    MxNId = TMath::Mx(NewNId+1, MxNId()); 
  }
  TNode& Node = NodeH.AddDat(NewNId);
  Node.Id = NewNId;
  Node.NIdV.GenExt(Pool.GetValVPt(NIdVId), Pool.GetVLen(NIdVId));
  Node.NIdV.Sort();
  NEdges += Node.GetDeg();
  return NewNId;
}

int TUNGraph::AddNodeUnchecked

(

int

NId = -1

)

Adds a node of ID NId to the network, noop if the node already exists.

Returns -1, if the node NId already exists. Otherwise, it returns the ID of the node being added. If NId is -1, node ID is automatically assigned.

Definition at line 20 of file graph.cpp.

                                      {
  if (IsNode(NId)) { return -1;}
  MxNId = TMath::Mx(NId+1, MxNId());
  NodeH.AddDat(NId, TNode(NId));
  return NId;
}

TEdgeI TUNGraph::BegEI ( ) const

inline

Returns an iterator referring to the first edge in the graph.

Definition at line 274 of file graph.h.

{ TNodeI NI = BegNI(); TEdgeI EI(NI, EndNI(), 0); if (GetNodes() != 0 && (NI.GetOutDeg()==0 || NI.GetId()>NI.GetOutNId(0))) { EI++; } return EI; }

TNodeI TUNGraph::BegNI ( ) const

inline

Returns an iterator referring to the first node in the graph.

Definition at line 237 of file graph.h.

{ return TNodeI(NodeH.BegI()); }

void TUNGraph::Clr ( )

inline

Deletes all nodes and edges from the graph.

Definition at line 294 of file graph.h.

{ MxNId=0; NEdges=0; NodeH.Clr(); }

void TUNGraph::Defrag

(

const bool &

OnlyNodeLinks = false

)

Defragments the graph.

After performing many node and edge insertions and deletions to a graph, the graph data structure will be fragmented in memory. This function compacts down the graph data structure and frees unneeded memory.

Definition at line 160 of file graph.cpp.

                                               {
  for (int n = NodeH.FFirstKeyId(); NodeH.FNextKeyId(n); ) {
    NodeH[n].NIdV.Pack();
  }
  if (! OnlyNodeLinks && ! NodeH.IsKeyIdEqKeyN()) {
    NodeH.Defrag();
  }
}

void TUNGraph::DelEdge	(	const int &	SrcNId,
		const int &	DstNId
	)

Deletes an edge between node IDs SrcNId and DstNId from the graph.

If the edge (SrcNId, DstNId) does not exist in the graph function still completes. But the function aborts if SrcNId or DstNId are not nodes in the graph.

Definition at line 124 of file graph.cpp.

                                                           {
  IAssertR(IsNode(SrcNId) && IsNode(DstNId), TStr::Fmt("%d or %d not a node.", SrcNId, DstNId).CStr());
  { TNode& N = GetNode(SrcNId);
  const int n = N.NIdV.SearchBin(DstNId);
  if (n!= -1) { N.NIdV.Del(n);  NEdges--; } }
  if (SrcNId != DstNId) { // not a self edge
    TNode& N = GetNode(DstNId);
    const int n = N.NIdV.SearchBin(SrcNId);
    if (n!= -1) { N.NIdV.Del(n); }
  }
}

void TUNGraph::DelNode

(

const int &

NId

)

Deletes node of ID NId from the graph.

If the node of ID NId does not exist the function aborts.

Definition at line 67 of file graph.cpp.

                                     {
  { AssertR(IsNode(NId), TStr::Fmt("NodeId %d does not exist", NId));
  TNode& Node = GetNode(NId);
  NEdges -= Node.GetDeg();
  for (int e = 0; e < Node.GetDeg(); e++) {
    const int nbr = Node.GetNbrNId(e);
    if (nbr == NId) { continue; }
    TNode& N = GetNode(nbr);
    const int n = N.NIdV.SearchBin(NId);
    IAssert(n != -1); // if NId points to N, then N also should point back
    if (n!= -1) { N.NIdV.Del(n); }
  } }
  NodeH.DelKey(NId);
}

void TUNGraph::DelNode ( const TNode &  NodeI )

inline

Deletes node of ID NodeI.GetId() from the graph.

Definition at line 233 of file graph.h.

{ DelNode(NodeI.GetId()); }

void TUNGraph::Dump

(

FILE *

OutF = stdout

)

const

Print the graph in a human readable form to an output stream OutF.

Definition at line 207 of file graph.cpp.

                                    {
  const int NodePlaces = (int) ceil(log10((double) GetNodes()));
  fprintf(OutF, "-------------------------------------------------\nUndirected Node Graph: nodes: %d, edges: %d\n", GetNodes(), GetEdges());
  for (int N = NodeH.FFirstKeyId(); NodeH.FNextKeyId(N); ) {
    const TNode& Node = NodeH[N];
    fprintf(OutF, "  %*d [%d] ", NodePlaces, Node.GetId(), Node.GetDeg());
    for (int edge = 0; edge < Node.GetDeg(); edge++) {
      fprintf(OutF, " %*d", NodePlaces, Node.GetNbrNId(edge)); }
    fprintf(OutF, "\n");
  }
  fprintf(OutF, "\n");
}

bool TUNGraph::Empty ( ) const

inline

Tests whether the graph is empty (has zero nodes).

Definition at line 292 of file graph.h.

{ return GetNodes()==0; }

TEdgeI TUNGraph::EndEI ( ) const

inline

Returns an iterator referring to the past-the-end edge in the graph.

Definition at line 276 of file graph.h.

{ return TEdgeI(EndNI(), EndNI()); }

TNodeI TUNGraph::EndNI ( ) const

inline

Returns an iterator referring to the past-the-end node in the graph.

Definition at line 239 of file graph.h.

{ return TNodeI(NodeH.EndI()); }

int TUNGraph::GetEdges

(

)

const

Returns the number of edges in the graph.

Definition at line 82 of file graph.cpp.

                             {
  //int Edges = 0;
  //for (int N=NodeH.FFirstKeyId(); NodeH.FNextKeyId(N); ) {
  //  Edges += NodeH[N].GetDeg();
  //}
  //return Edges/2;
  return NEdges;
}

TEdgeI TUNGraph::GetEI

(

const int &

EId

)

const

Not supported/implemented!

TUNGraph::TEdgeI TUNGraph::GetEI	(	const int &	SrcNId,
		const int &	DstNId
	)		const

Returns an iterator referring to edge (SrcNId, DstNId) in the graph.

Note that since this is an undirected graph GetEI(SrcNId, DstNId) has the same effect as GetEI(DstNId, SrcNId).

Definition at line 143 of file graph.cpp.

                                                                         {
  const int MnNId = TMath::Mn(SrcNId, DstNId);
  const int MxNId = TMath::Mx(SrcNId, DstNId);
  const TNodeI SrcNI = GetNI(MnNId);
  const int NodeN = SrcNI.NodeHI.GetDat().NIdV.SearchBin(MxNId);
  IAssert(NodeN != -1);
  return TEdgeI(SrcNI, EndNI(), NodeN);
}

int TUNGraph::GetMxNId ( ) const

inline

Returns an ID that is larger than any node ID in the graph.

Definition at line 243 of file graph.h.

{ return MxNId; }

TNodeI TUNGraph::GetNI ( const int &  NId ) const

inline

Returns an iterator referring to the node of ID NId in the graph.

Definition at line 241 of file graph.h.

{ return TNodeI(NodeH.GetI(NId)); }

void TUNGraph::GetNIdV

(

TIntV &

NIdV

)

const

Gets a vector IDs of all nodes in the graph.

Definition at line 153 of file graph.cpp.

                                        {
  NIdV.Gen(GetNodes(), 0);
  for (int N=NodeH.FFirstKeyId(); NodeH.FNextKeyId(N); ) {
    NIdV.Add(NodeH.GetKey(N)); }
}

TNode& TUNGraph::GetNode ( const int &  NId )

inlineprivate

Definition at line 153 of file graph.h.

{ return NodeH.GetDat(NId); }

const TNode& TUNGraph::GetNode ( const int &  NId ) const

inlineprivate

Definition at line 154 of file graph.h.

{ return NodeH.GetDat(NId); }

int TUNGraph::GetNodes ( ) const

inline

Returns the number of nodes in the graph.

Definition at line 192 of file graph.h.

{ return NodeH.Len(); }

TNodeI TUNGraph::GetRndNI ( TRnd &  Rnd = TInt::Rnd )

inline

Returns an interator referring to a random node in the graph.

Definition at line 287 of file graph.h.

{ return GetNI(GetRndNId(Rnd)); }

int TUNGraph::GetRndNId ( TRnd &  Rnd = TInt::Rnd )

inline

Returns an ID of a random node in the graph.

Definition at line 285 of file graph.h.

{ return NodeH.GetKey(NodeH.GetRndKeyId(Rnd, 0.8)); }

PUNGraph TUNGraph::GetSmallGraph ( )

static

Returns a small graph on 5 nodes and 5 edges.

/// Graph:   3--0--4
///            /|
///           1-2
/// 

Definition at line 221 of file graph.cpp.

                                 {
  PUNGraph Graph = TUNGraph::New();
  for (int i = 0; i < 5; i++) { Graph->AddNode(i); }
  Graph->AddEdge(0,1);  Graph->AddEdge(0,2);
  Graph->AddEdge(0,3);  Graph->AddEdge(0,4);
  Graph->AddEdge(1,2);
  return Graph;
}

bool TUNGraph::HasFlag

(

const TGraphFlag &

Flag

)

const

Allows for run-time checking the type of the graph (see the TGraphFlag for flags).

Definition at line 3 of file graph.cpp.

                                                   {
  return HasGraphFlag(TUNGraph::TNet, Flag);
}

bool TUNGraph::IsEdge	(	const int &	SrcNId,
		const int &	DstNId
	)		const

Tests whether an edge between node IDs SrcNId and DstNId exists in the graph.

Definition at line 137 of file graph.cpp.

                                                                {
  if (! IsNode(SrcNId) || ! IsNode(DstNId)) return false;
  return GetNode(SrcNId).IsNbrNId(DstNId);
}

bool TUNGraph::IsNode ( const int &  NId ) const

inline

Tests whether ID NId is a node.

Definition at line 235 of file graph.h.

{ return NodeH.IsKey(NId); }

bool TUNGraph::IsOk

(

const bool &

ThrowExcept = true

)

const

Checks the graph data structure for internal consistency.

For each node in the graph check that its neighbors are also nodes in the graph.

Definition at line 170 of file graph.cpp.

                                                 {
  bool RetVal = true;
  for (int N = NodeH.FFirstKeyId(); NodeH.FNextKeyId(N); ) {
    const TNode& Node = NodeH[N];
    if (! Node.NIdV.IsSorted()) {
      const TStr Msg = TStr::Fmt("Neighbor list of node %d is not sorted.", Node.GetId());
      if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); }
      RetVal=false;
    }
    int prevNId = -1;
    for (int e = 0; e < Node.GetDeg(); e++) {
      if (! IsNode(Node.GetNbrNId(e))) {
        const TStr Msg = TStr::Fmt("Edge %d --> %d: node %d does not exist.",
          Node.GetId(), Node.GetNbrNId(e), Node.GetNbrNId(e));
        if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); }
        RetVal=false;
      }
      if (e > 0 && prevNId == Node.GetNbrNId(e)) {
        const TStr Msg = TStr::Fmt("Node %d has duplicate edge %d --> %d.",
          Node.GetId(), Node.GetId(), Node.GetNbrNId(e));
        if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); }
        RetVal=false;
      }
      prevNId = Node.GetNbrNId(e);
    }
  }
  int EdgeCnt = 0;
  for (TEdgeI EI = BegEI(); EI < EndEI(); EI++) { EdgeCnt++; }
  if (EdgeCnt != GetEdges()) {
    const TStr Msg = TStr::Fmt("Number of edges counter is corrupted: GetEdges():%d, EdgeCount:%d.", GetEdges(), EdgeCnt);
    if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); }
    RetVal=false;
  }
  return RetVal;
}

static PUNGraph TUNGraph::Load ( TSIn &  SIn )

inlinestatic

Static constructor that loads the graph from a stream SIn and returns a pointer to it.

Definition at line 178 of file graph.h.

{ return PUNGraph(new TUNGraph(SIn)); }

void TUNGraph::LoadGraphShM ( TShMIn &  ShMIn )

inlineprivate

Definition at line 155 of file graph.h.

                                   {
    MxNId = TInt(ShMIn);
    NEdges = TInt(ShMIn);
    TLoadTNodeInitializer Fn;
    NodeH.LoadShM(ShMIn, Fn);
  }

static PUNGraph TUNGraph::LoadShM ( TShMIn &  ShMIn )

inlinestatic

Static constructor that loads the graph from shared memory.

Cannot perform operations that edit the edge vectors of nodes or perform illegal operations on the NodeH (deletion or swapping keys)

Definition at line 182 of file graph.h.

                                         {
    TUNGraph* Graph = new TUNGraph();
    Graph->LoadGraphShM(ShMIn);
    return PUNGraph(Graph);
  }  

static PUNGraph TUNGraph::New ( )

inlinestatic

Static constructor that returns a pointer to the graph. Call: PUNGraph Graph = TUNGraph::New().

Definition at line 172 of file graph.h.

{ return new TUNGraph(); }

static PUNGraph TUNGraph::New ( const int &  Nodes, const int &  Edges  )

inlinestatic

Static constructor that returns a pointer to the graph and reserves enough memory for Nodes nodes and Edges edges.

Call: PUNGraph Graph = TUNGraph::New(Nodes, Edges).

Definition at line 176 of file graph.h.

{ return new TUNGraph(Nodes, Edges); }

TUNGraph& TUNGraph::operator= ( const TUNGraph &  Graph )

inline

Definition at line 188 of file graph.h.

                                               {
    if (this!=&Graph) { MxNId=Graph.MxNId; NEdges=Graph.NEdges; NodeH=Graph.NodeH; } return *this; }

void TUNGraph::Reserve ( const int &  Nodes, const int &  Edges  )

inline

Reserves memory for a graph of Nodes nodes and Edges edges.

Definition at line 298 of file graph.h.

{ if (Nodes>0) NodeH.Gen(Nodes/2); }

void TUNGraph::ReserveNIdDeg ( const int &  NId, const int &  Deg  )

inline

Reserves memory for node ID NId having Deg edges.

Definition at line 300 of file graph.h.

{ GetNode(NId).NIdV.Reserve(Deg); }

void TUNGraph::Save ( TSOut &  SOut ) const

inline

Saves the graph to a (binary) stream SOut.

Definition at line 170 of file graph.h.

{ MxNId.Save(SOut); NEdges.Save(SOut); NodeH.Save(SOut); }

void TUNGraph::SortNodeAdjV ( )

inline

Sorts the adjacency lists of each node.

Definition at line 296 of file graph.h.

{ for (TNodeI NI = BegNI(); NI < EndNI(); NI++) { NI.SortNIdV();} }

Friends And Related Function Documentation

friend class TPt< TUNGraph >

friend

Definition at line 323 of file graph.h.

friend class TUNGraphMtx

friend

Definition at line 322 of file graph.h.

Member Data Documentation

TCRef TUNGraph::CRef

private

Definition at line 143 of file graph.h.

TInt TUNGraph::MxNId

private

Definition at line 144 of file graph.h.

TInt TUNGraph::NEdges

private

Definition at line 144 of file graph.h.

THash<TInt, TNode> TUNGraph::NodeH

private

Definition at line 145 of file graph.h.

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The documentation for this class was generated from the following files:

• snap-core/graph.h
• snap-core/graph.cpp