TNGraphMP Class Reference

Directed graph for multi-threaded operations. More...

#include <graphmp.h>

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

Public Types
typedef TNGraphMP	TNet
typedef TPt< TNGraphMP >	PNet

Public Member Functions
	TNGraphMP ()
	TNGraphMP (const int &Nodes, const int &Edges)
	Constructor that reserves enough memory for a graph of Nodes nodes and Edges edges. More...
	TNGraphMP (const TNGraphMP &Graph)
	TNGraphMP (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...
TNGraphMP &	operator= (const TNGraphMP &Graph)
int	GetNodes () const
	Returns the number of nodes in the graph. More...
void	SetNodes (const int &Length)
	Sets 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 graph without performing checks. More...
int	AddNode (const TNodeI &NodeId)
	Adds a node of ID NodeI.GetId() to the graph. More...
int	AddNode (const int &NId, const TIntV &InNIdV, const TIntV &OutNIdV)
	Adds a node of ID NId to the graph, creates edges to the node from all nodes in vector InNIdV, creates edges from the node to all nodes in vector OutNIdV. More...
int	AddNode (const int &NId, const TVecPool< TInt > &Pool, const int &SrcVId, const int &DstVId)
	Adds a node of ID NId to the graph, creates edges to the node from all nodes in vector InNIdV in the vector pool Pool, creates edges from the node to all nodes in vector OutNIdVin 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 the maximum id of a any node in the graph. More...
int	Reserved () const
int	GetEdges () const
	Returns the number of edges in the graph. More...
int	AddEdge (const int &SrcNId, const int &DstNId)
	Adds an edge from node IDs SrcNId to node DstNId to the graph. More...
int	AddEdgeUnchecked (const int &SrcNId, const int &DstNId)
	Adds an edge from node IDs SrcNId to node DstNId to the graph without performing checks. More...
int	AddEdge (const TEdgeI &EdgeI)
	Adds an edge from EdgeI.GetSrcNId() to EdgeI.GetDstNId() to the graph. More...
int	AddOutEdge1 (int &SrcIdx, const int &SrcNId, const int &DstNId)
int	AddInEdge1 (int &DstIdx, const int &SrcNId, const int &DstNId)
void	AddOutEdge2 (const int &SrcNId, const int &DstNId)
void	AddInEdge2 (const int &SrcNId, const int &DstNId)
void	AddNodeWithEdges (const TInt &NId, TIntV &InNIdV, TIntV &OutNIdV)
	Adds a node of ID NId to the graph, creates edges to the node from all nodes in vector InNIdV, creates edges from the node to all nodes in vector OutNIdV. More...
void	DelEdge (const int &SrcNId, const int &DstNId, const bool &IsDir=true)
	Deletes an edge from node IDs SrcNId to DstNId from the graph. More...
bool	IsEdge (const int &SrcNId, const int &DstNId, const bool &IsDir=true) const
	Tests whether an edge from node IDs SrcNId to 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 &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	Reserve (const int &Nodes, const int &Edges)
	Reserves memory for a graph of Nodes nodes and Edges edges. More...
void	ReserveNodeDegs (const int &Idx, const int &InDeg, const int &OutDeg)
	Reserves memory for node Idx having InDeg in-edges and OutDeg out-edges. More...
void	ReserveNIdInDeg (const int &NId, const int &InDeg)
	Reserves memory for node ID NId having InDeg in-edges. More...
void	ReserveNIdOutDeg (const int &NId, const int &OutDeg)
	Reserves memory for node ID NId having OutDeg out-edges. More...
void	SortEdges (const int &Idx, const int &InDeg, const int &OutDeg)
	Sorts in-edges and out-edges. More...
void	SortNodeAdjV ()
	Sorts the adjacency lists of each node. 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 PNGraphMP	New ()
	Static constructor that returns a pointer to the graph. Call: PNGraphMP Graph = TNGraphMP::New(). More...
static PNGraphMP	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 PNGraphMP	Load (TSIn &SIn)
	Static constructor that loads the graph from a stream SIn and returns a pointer to it. More...
static PNGraphMP	GetSmallGraph ()
	Returns a small graph on 5 nodes and 6 edges. More...

Private Member Functions
TNode &	GetNode (const int &NId)
const TNode &	GetNode (const int &NId) const

Private Attributes
TCRef	CRef
TInt	MxNId
THashMP< TInt, TNode >	NodeH

Friends
class	TPt< TNGraphMP >
class	TNGraphMPMtx

Detailed Description

Directed graph for multi-threaded operations.

Node IDs can be arbitrary non-negative integers. Nodes and edges have no attributes/data associated with them. There is at most one directed edge from one source node to a destination node. There can be an edge between the same pair of nodes in the opposite direction. Self loops (one per node) are allowed but multiple (parallel) edges are not. The directed 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 24 of file graphmp.h.

Member Typedef Documentation

typedef TPt<TNGraphMP> TNGraphMP::PNet

Definition at line 27 of file graphmp.h.

typedef TNGraphMP TNGraphMP::TNet

Definition at line 26 of file graphmp.h.

Constructor & Destructor Documentation

TNGraphMP::TNGraphMP ( )

inline

Definition at line 129 of file graphmp.h.

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

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

inlineexplicit

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

Definition at line 131 of file graphmp.h.

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

TNGraphMP::TNGraphMP ( const TNGraphMP &  Graph )

inline

Definition at line 132 of file graphmp.h.

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

TNGraphMP::TNGraphMP ( TSIn &  SIn )

inline

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

Definition at line 134 of file graphmp.h.

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

Member Function Documentation

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

Adds an edge from node IDs SrcNId to node 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 TNGraphMP have no IDs we return -1. Function aborts if SrcNId or DstNId are not nodes in the graph.

Definition at line 97 of file graphmp.cpp.

                                                           {
  IAssertR(IsNode(SrcNId) && IsNode(DstNId), TStr::Fmt("%d or %d not a node.", SrcNId, DstNId).CStr());
  //IAssert(! IsEdge(SrcNId, DstNId));
  if (IsEdge(SrcNId, DstNId)) { return -2; }
  GetNode(SrcNId).OutNIdV.AddSorted(DstNId);
  GetNode(DstNId).InNIdV.AddSorted(SrcNId);
  return -1; // edge id
}

int TNGraphMP::AddEdge ( const TEdgeI &  EdgeI )

inline

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

Definition at line 218 of file graphmp.h.

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

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

Adds an edge from node IDs SrcNId to node DstNId to the graph without performing checks.

Definition at line 106 of file graphmp.cpp.

                                                                    {
  GetNode(SrcNId).OutNIdV.Add(DstNId);
  GetNode(DstNId).InNIdV.Add(SrcNId);
  return -1; // edge id
}

int TNGraphMP::AddInEdge1	(	int &	DstIdx,
		const int &	SrcNId,
		const int &	DstNId
	)

Definition at line 253 of file graphmp.cpp.

                                                                           {
  bool Found;
  int DstKeyId;

  //DstKeyId = NodeH.AddKey2(DstIdx, DstNId, Found);
  DstKeyId = NodeH.AddKey12(DstIdx, DstNId, Found);
  if (!Found) {
    NodeH[DstKeyId] = TNode(DstNId);
    //MxNId = TMath::Mx(DstNId+1, MxNId());
  }
  //GetNode(DstNId).InNIdV.Add(SrcNId);
  //NodeH[DstKeyId].InNIdV.Add1(SrcNId);

  // TODO:RS, edge lists need to be sorted at the end

  DstIdx = DstKeyId;
  return Found;
}

void TNGraphMP::AddInEdge2	(	const int &	SrcNId,
		const int &	DstNId
	)

Definition at line 276 of file graphmp.cpp.

                                                               {
  NodeH[NodeH.GetKeyId(DstNId)].InNIdV.AddMP(SrcNId);
}

int TNGraphMP::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 10 of file graphmp.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 TNGraphMP::AddNode ( const TNodeI &  NodeId )

inline

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

Definition at line 163 of file graphmp.h.

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

int TNGraphMP::AddNode	(	const int &	NId,
		const TIntV &	InNIdV,
		const TIntV &	OutNIdV
	)

Adds a node of ID NId to the graph, creates edges to the node from all nodes in vector InNIdV, creates edges from the node to all nodes in vector OutNIdV.

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 vectors InNIdV and OutNIdV do not exist. Use TNGraphMP::IsOk to check that the resulting graph is consistent after the operation.

Definition at line 30 of file graphmp.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.InNIdV = InNIdV;
  Node.OutNIdV = OutNIdV;
  Node.InNIdV.Sort();
  Node.OutNIdV.Sort();
  return NewNId;
}

int TNGraphMP::AddNode	(	const int &	NId,
		const TVecPool< TInt > &	Pool,
		const int &	SrcVId,
		const int &	DstVId
	)

Adds a node of ID NId to the graph, creates edges to the node from all nodes in vector InNIdV in the vector pool Pool, creates edges from the node to all nodes in vector OutNIdVin 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 TNGraphMP::IsOk to check that the resulting graph is consistent.

Definition at line 50 of file graphmp.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.InNIdV.GenExt(Pool.GetValVPt(SrcVId), Pool.GetVLen(SrcVId));
  Node.OutNIdV.GenExt(Pool.GetValVPt(DstVId), Pool.GetVLen(DstVId));
  Node.InNIdV.Sort();
  Node.OutNIdV.Sort();
  return NewNId;
}

int TNGraphMP::AddNodeUnchecked

(

int

NId = -1

)

Adds a node of ID NId to the graph without performing checks.

Definition at line 21 of file graphmp.cpp.

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

void TNGraphMP::AddNodeWithEdges	(	const TInt &	NId,
		TIntV &	InNIdV,
		TIntV &	OutNIdV
	)

Adds a node of ID NId to the graph, creates edges to the node from all nodes in vector InNIdV, creates edges from the node to all nodes in vector OutNIdV.

Definition at line 282 of file graphmp.cpp.

                                                                               {
  int NodeIdx = abs((NId.GetPrimHashCd()) % Reserved());
  int NodeKeyId = NodeH.AddKey13(NodeIdx, NId);
  NodeH[NodeKeyId] = TNode(NId);
  NodeH[NodeKeyId].InNIdV.MoveFrom(InNIdV);
  NodeH[NodeKeyId].OutNIdV.MoveFrom(OutNIdV);  
}

int TNGraphMP::AddOutEdge1	(	int &	SrcIdx,
		const int &	SrcNId,
		const int &	DstNId
	)

Definition at line 234 of file graphmp.cpp.

                                                                            {
  bool Found;
  int SrcKeyId;

  //SrcKeyId = NodeH.AddKey2(SrcIdx, SrcNId, Found);
  SrcKeyId = NodeH.AddKey12(SrcIdx, SrcNId, Found);
  if (!Found) {
    NodeH[SrcKeyId] = TNode(SrcNId);
    //MxNId = TMath::Mx(SrcNId+1, MxNId());
  }
  //GetNode(SrcNId).OutNIdV.Add(DstNId);
  //NodeH[SrcKeyId].OutNIdV.Add1(DstNId);

  // TODO:RS, edge lists need to be sorted at the end

  SrcIdx = SrcKeyId;
  return Found;
}

void TNGraphMP::AddOutEdge2	(	const int &	SrcNId,
		const int &	DstNId
	)

Definition at line 272 of file graphmp.cpp.

                                                                {
  NodeH[NodeH.GetKeyId(SrcNId)].OutNIdV.AddMP(DstNId);
}

TEdgeI TNGraphMP::BegEI ( ) const

inline

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

Definition at line 236 of file graphmp.h.

{ TNodeI NI=BegNI(); while(NI<EndNI() && NI.GetOutDeg()==0){NI++;} return TEdgeI(NI, EndNI()); }

TNodeI TNGraphMP::BegNI ( ) const

inline

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

Definition at line 194 of file graphmp.h.

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

void TNGraphMP::Clr ( )

inline

Deletes all nodes and edges from the graph.

Definition at line 254 of file graphmp.h.

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

void TNGraphMP::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 149 of file graphmp.cpp.

                                                {
#if 0
  for (int n = NodeH.FFirstKeyId(); NodeH.FNextKeyId(n); ) {
    TNode& Node = NodeH[n];
    Node.InNIdV.Pack();  Node.OutNIdV.Pack();
  }
  if (! OnlyNodeLinks && ! NodeH.IsKeyIdEqKeyN()) { NodeH.Defrag(); }
#endif
}

void TNGraphMP::DelEdge	(	const int &	SrcNId,
		const int &	DstNId,
		const bool &	IsDir = true
	)

Deletes an edge from node IDs SrcNId to 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 112 of file graphmp.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.OutNIdV.SearchBin(DstNId);
  if (n!= -1) { N.OutNIdV.Del(n); } }
  { TNode& N = GetNode(DstNId);
  const int n = N.InNIdV.SearchBin(SrcNId);
  if (n!= -1) { N.InNIdV.Del(n); } }
  if (! IsDir) {
    { TNode& N = GetNode(SrcNId);
    const int n = N.InNIdV.SearchBin(DstNId);
    if (n!= -1) { N.InNIdV.Del(n); } }
    { TNode& N = GetNode(DstNId);
    const int n = N.OutNIdV.SearchBin(SrcNId);
    if (n!= -1) { N.OutNIdV.Del(n); } }
  }
}

void TNGraphMP::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 68 of file graphmp.cpp.

                                      {
#if 0
  { TNode& Node = GetNode(NId);
  for (int e = 0; e < Node.GetOutDeg(); e++) {
  const int nbr = Node.GetOutNId(e);
  if (nbr == NId) { continue; }
    TNode& N = GetNode(nbr);
    const int n = N.InNIdV.SearchBin(NId);
    if (n!= -1) { N.InNIdV.Del(n); }
  }
  for (int e = 0; e < Node.GetInDeg(); e++) {
  const int nbr = Node.GetInNId(e);
  if (nbr == NId) { continue; }
    TNode& N = GetNode(nbr);
    const int n = N.OutNIdV.SearchBin(NId);
    if (n!= -1) { N.OutNIdV.Del(n); }
  } }
  NodeH.DelKey(NId);
#endif
}

void TNGraphMP::DelNode ( const TNode &  NodeI )

inline

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

Definition at line 190 of file graphmp.h.

{ DelNode(NodeI.GetId()); }

void TNGraphMP::Dump

(

FILE *

OutF = stdout

)

const

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

Definition at line 206 of file graphmp.cpp.

                                     {
  const int NodePlaces = (int) ceil(log10((double) GetNodes()));
  fprintf(OutF, "-------------------------------------------------\nDirected 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]\n", NodePlaces, Node.GetId());
    fprintf(OutF, "    in [%d]", Node.GetInDeg());
    for (int edge = 0; edge < Node.GetInDeg(); edge++) {
      fprintf(OutF, " %*d", NodePlaces, Node.GetInNId(edge)); }
    fprintf(OutF, "\n    out[%d]", Node.GetOutDeg());
    for (int edge = 0; edge < Node.GetOutDeg(); edge++) {
      fprintf(OutF, " %*d", NodePlaces, Node.GetOutNId(edge)); }
    fprintf(OutF, "\n");
  }
  fprintf(OutF, "\n");
}

bool TNGraphMP::Empty ( ) const

inline

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

Definition at line 252 of file graphmp.h.

{ return GetNodes()==0; }

TEdgeI TNGraphMP::EndEI ( ) const

inline

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

Definition at line 238 of file graphmp.h.

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

TNodeI TNGraphMP::EndNI ( ) const

inline

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

Definition at line 196 of file graphmp.h.

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

int TNGraphMP::GetEdges

(

)

const

Returns the number of edges in the graph.

Definition at line 89 of file graphmp.cpp.

                              {
  int edges=0;
  for (int N=NodeH.FFirstKeyId(); NodeH.FNextKeyId(N); ) {
    edges+=NodeH[N].GetOutDeg();
  }
  return edges;
}

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

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

Definition at line 136 of file graphmp.cpp.

                                                                           {
  const TNodeI SrcNI = GetNI(SrcNId);
  const int NodeN = SrcNI.NodeHI.GetDat().OutNIdV.SearchBin(DstNId);
  IAssert(NodeN != -1);
  return TEdgeI(SrcNI, EndNI(), NodeN);
}

int TNGraphMP::GetMxNId ( ) const

inline

Returns the maximum id of a any node in the graph.

Definition at line 202 of file graphmp.h.

{ return MxNId; }

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

inline

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

Definition at line 198 of file graphmp.h.

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

void TNGraphMP::GetNIdV

(

TIntV &

NIdV

)

const

Gets a vector IDs of all nodes in the graph.

Definition at line 143 of file graphmp.cpp.

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

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

inlineprivate

Definition at line 126 of file graphmp.h.

{ return NodeH.GetDat(NId); }

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

inlineprivate

Definition at line 127 of file graphmp.h.

{ return NodeH.GetDat(NId); }

int TNGraphMP::GetNodes ( ) const

inline

Returns the number of nodes in the graph.

Definition at line 151 of file graphmp.h.

{ return NodeH.Len(); }

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

inline

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

Definition at line 247 of file graphmp.h.

{ return GetNI(GetRndNId(Rnd)); }

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

inline

Returns an ID of a random node in the graph.

Definition at line 245 of file graphmp.h.

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

PNGraphMP TNGraphMP::GetSmallGraph ( )

static

Returns a small graph on 5 nodes and 6 edges.

/// Edges:  0 -> 1, 1 -> 2, 0 -> 2, 1 -> 3, 3 -> 4, 2 -> 3
/// 

Definition at line 223 of file graphmp.cpp.

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

bool TNGraphMP::HasFlag

(

const TGraphFlag &

Flag

)

const

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

Definition at line 6 of file graphmp.cpp.

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

bool TNGraphMP::IsEdge	(	const int &	SrcNId,
		const int &	DstNId,
		const bool &	IsDir = true
	)		const

Tests whether an edge from node IDs SrcNId to DstNId exists in the graph.

Definition at line 130 of file graphmp.cpp.

                                                                                    {
  if (! IsNode(SrcNId) || ! IsNode(DstNId)) { return false; }
  if (IsDir) { return GetNode(SrcNId).IsOutNId(DstNId); }
  else { return GetNode(SrcNId).IsOutNId(DstNId) || GetNode(DstNId).IsOutNId(SrcNId); }
}

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

inline

Tests whether ID NId is a node.

Definition at line 192 of file graphmp.h.

{ return NodeH.IsKey(NId); }

bool TNGraphMP::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 160 of file graphmp.cpp.

                                                  {
  bool RetVal = true;
  for (int N = NodeH.FFirstKeyId(); NodeH.FNextKeyId(N); ) {
    const TNode& Node = NodeH[N];
    if (! Node.OutNIdV.IsSorted()) {
      const TStr Msg = TStr::Fmt("Out-neighbor list of node %d is not sorted.", Node.GetId());
      if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); } RetVal=false;
    }
    if (! Node.InNIdV.IsSorted()) {
      const TStr Msg = TStr::Fmt("In-neighbor list of node %d is not sorted.", Node.GetId());
      if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); } RetVal=false;
    }
    // check out-edges
    int prevNId = -1;
    for (int e = 0; e < Node.GetOutDeg(); e++) {
      if (! IsNode(Node.GetOutNId(e))) {
        const TStr Msg = TStr::Fmt("Out-edge %d --> %d: node %d does not exist.",
          Node.GetId(), Node.GetOutNId(e), Node.GetOutNId(e));
        if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); } RetVal=false;
      }
      if (e > 0 && prevNId == Node.GetOutNId(e)) {
        const TStr Msg = TStr::Fmt("Node %d has duplidate out-edge %d --> %d.",
          Node.GetId(), Node.GetId(), Node.GetOutNId(e));
        if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); } RetVal=false;
      }
      prevNId = Node.GetOutNId(e);
    }
    // check in-edges
    prevNId = -1;
    for (int e = 0; e < Node.GetInDeg(); e++) {
      if (! IsNode(Node.GetInNId(e))) {
        const TStr Msg = TStr::Fmt("In-edge %d <-- %d: node %d does not exist.",
          Node.GetId(), Node.GetInNId(e), Node.GetInNId(e));
        if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); } RetVal=false;
      }
      if (e > 0 && prevNId == Node.GetInNId(e)) {
        const TStr Msg = TStr::Fmt("Node %d has duplidate in-edge %d <-- %d.",
          Node.GetId(), Node.GetId(), Node.GetInNId(e));
        if (ThrowExcept) { EAssertR(false, Msg); } else { ErrNotify(Msg.CStr()); } RetVal=false;
      }
      prevNId = Node.GetInNId(e);
    }
  }
  return RetVal;
}

static PNGraphMP TNGraphMP::Load ( TSIn &  SIn )

inlinestatic

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

Definition at line 144 of file graphmp.h.

{ return PNGraphMP(new TNGraphMP(SIn)); }

static PNGraphMP TNGraphMP::New ( )

inlinestatic

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

Definition at line 138 of file graphmp.h.

{ return new TNGraphMP(); }

static PNGraphMP TNGraphMP::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: PNGraphMP Graph = TNGraphMP::New(Nodes, Edges).

Definition at line 142 of file graphmp.h.

{ return new TNGraphMP(Nodes, Edges); }

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

inline

Definition at line 147 of file graphmp.h.

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

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

inline

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

Definition at line 256 of file graphmp.h.

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

int TNGraphMP::Reserved ( ) const

inline

Definition at line 203 of file graphmp.h.

{return NodeH.GetReservedKeyIds();}

void TNGraphMP::ReserveNIdInDeg ( const int &  NId, const int &  InDeg  )

inline

Reserves memory for node ID NId having InDeg in-edges.

Definition at line 260 of file graphmp.h.

{ GetNode(NId).InNIdV.Reserve(InDeg); }

void TNGraphMP::ReserveNIdOutDeg ( const int &  NId, const int &  OutDeg  )

inline

Reserves memory for node ID NId having OutDeg out-edges.

Definition at line 262 of file graphmp.h.

{ GetNode(NId).OutNIdV.Reserve(OutDeg); }

void TNGraphMP::ReserveNodeDegs ( const int &  Idx, const int &  InDeg, const int &  OutDeg  )

inline

Reserves memory for node Idx having InDeg in-edges and OutDeg out-edges.

Definition at line 258 of file graphmp.h.

{ if (InDeg > 0) NodeH[Idx].InNIdV.Reserve(InDeg); if (OutDeg > 0) NodeH[Idx].OutNIdV.Reserve(OutDeg); }

void TNGraphMP::Save ( TSOut &  SOut ) const

inline

Saves the graph to a (binary) stream SOut.

Definition at line 136 of file graphmp.h.

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

void TNGraphMP::SetNodes ( const int &  Length )

inline

Sets the number of nodes in the graph.

Definition at line 153 of file graphmp.h.

{ NodeH.SetLen(Length); }

void TNGraphMP::SortEdges ( const int &  Idx, const int &  InDeg, const int &  OutDeg  )

inline

Sorts in-edges and out-edges.

Definition at line 264 of file graphmp.h.

{ if (InDeg > 0) NodeH[Idx].InNIdV.Sort(); if (OutDeg > 0) NodeH[Idx].OutNIdV.Sort(); }

void TNGraphMP::SortNodeAdjV ( )

inline

Sorts the adjacency lists of each node.

Definition at line 266 of file graphmp.h.

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

Friends And Related Function Documentation

friend class TNGraphMPMtx

friend

Definition at line 288 of file graphmp.h.

friend class TPt< TNGraphMP >

friend

Definition at line 287 of file graphmp.h.

Member Data Documentation

TCRef TNGraphMP::CRef

private

Definition at line 122 of file graphmp.h.

TInt TNGraphMP::MxNId

private

Definition at line 123 of file graphmp.h.

THashMP<TInt, TNode> TNGraphMP::NodeH

private

Definition at line 124 of file graphmp.h.

---

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

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