Graph and Network Classes

Graphs and networks in SNAP are represented as undirected graphs TUNGraph, directed graphs TNGraph and multigraphs with attributes TNEANet.

TUNGraph

class TUNGraph

class TUNGraph(Nodes, Edges)

class TUNGraph(Graph)

Returns a new undirected graph. If no parameters are provided, an empty graph is created. If Nodes and Edges are specified, space is preallocated for Nodes nodes and Edges edges. If Graph is specified, the new graph is a copy of the input graph.

Nodes have IDs, which are 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.

TUNGraph provides iterators for fast traversal of nodes and edges. Iterator classes are TUNGraphNodeI for iterating over nodes and TUNGraphEdgeI for iterating over edges.

TUNGraph provides the following methods:

New()

Returns a pointer to a new graph.

New(Nodes, Edges)

Returns a pointer to a new graph and reserves enough memory for Nodes nodes and Edges edges.

Load(SIn)

Loads a graph from a binary stream SIn and returns a pointer to it.

Save(SOut)

Saves the graph to a binary stream SOut.

GetNodes()

Returns the number of nodes in the graph.

AddNode(NId)

Adds a node of ID NId to the graph, NId is an integer. Returns node ID. If NId is -1, node ID is automatically assigned. It throws an exception, if a node with ID NId already exists.

AddNode(NodeI)

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

DelNode(NId)

Deletes node of ID NId from the graph. NId is an integer.

DelNode(NodeI)

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

IsNode(NId)

Returns true, if ID NId is a node in the graph.

BegNI()

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

EndNI()

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

GetNI(NId)

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

GetMxNId()

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

GetEdges()

Returns the number of edges in the graph.

AddEdge(SrcNId, DstNId)

Adds an edge between node IDs SrcNId and DstNId to the graph. Returns -1, if the edge was successfully added. Returns -2, if the edge already exists. The function throws an exception, if SrcNId or DstNId are not nodes in the graph.

AddEdge(EdgeI)

Adds an edge between EdgeI.GetSrcNId() and EdgeI.GetDstNId() to the graph. EdgeI is an edge iterator. Returns -1, if successful. Returns -2, otherwise.

DelEdge(SrcNId, DstNId)

Deletes an edge between node IDs SrcNId and DstNId from the graph. If the edge between SrcNId and DstNId does not exist in the graph, function still completes. But the function throws an exception, if SrcNId or DstNId are not nodes in the graph.

IsEdge(SrcNId, DstNId)

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

BegEI()

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

EndEI()

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

GetEI(SrcNId, DstNId)

Returns an edge iterator referring to edge between node IDs SrcNId and DstNId in the graph. Since this is an undirected graph GetEI(SrcNId, DstNId) has the same effect as GetEI(DstNId, SrcNId).

GetRndNId()

Returns an ID of a random node in the graph.

GetRndNI()

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

Empty()

Returns true if the graph is empty, has zero nodes.

Clr()

Deletes all nodes and edges from the graph.

Reserve(Nodes, Edges)

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

ReserveNIdDeg(NId, Deg)

Reserves memory for node ID NId having Deg edges.

HasFlag(Flag)

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

Defrag()

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

Dump(OutF=sys.stdout)

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

GetSmallGraph()

Returns a small graph on 5 nodes and 5 edges.

Below is some code demonstrating the use of the TUNGraph class:

>>> G1 = snap.TUNGraph.New()
>>> G1.AddNode(1)
1
>>> G1.AddNode(2)
2
>>> G1.AddNode(5)
5
>>> G1.AddEdge(1,5)
-1
>>> G1.AddEdge(1,2)
-1
>>> print G1.Empty()
False
>>> print G1.GetNodes()
3
>>> print G1.GetEdges()
2

TUNGraphNodeI

class TUNGraphNodeI

Returns a new node iterator for TUNGraph. Normally, these objects are not created directly, but obtained via a call to the graph class TUNGraph method, such as BegNI(), that returns a node iterator.

TUNGraphNodeI provides the following methods:

Next()

Moves the iterator to the next node in the graph.

GetId()

Returns node ID of the current node.

GetDeg()

GetInDeg()

GetOutDeg()

Returns degree of the current node. Since the graph is undirected, all three methods return the same value.

GetInNId(NodeN)

Returns ID of NodeN-th in-node (the node pointing to the current node).

GetOutNId(NodeN)

Returns ID of NodeN-th out-node (the node the current node points to).

GetNbrNId(NodeN)

Returns ID of NodeN-th neighboring node.

IsInNId(NId)

Tests whether node with ID NId points to the current node.

IsOutNId(NId)

Tests whether the current node points to node with ID NId.

IsNbrNId(NId)

Tests whether node with ID NId is a neighbor of the current node.

TUNGraphEdgeI

class TUNGraphEdgeI

Returns a new edge iterator for TUNGraph. Normally, these objects are not created directly, but obtained via a call to the graph class TUNGraph method, such as BegEI(), that returns an edge iterator.

TUNGraphEdgeI provides the following methods:

Next()

Moves the iterator to the next edge in the graph.

GetId()

Always returns -1 for TUNGraph, since edges do not have explicit IDs.

GetSrcNId()

Returns the ID of the source node of the edge. Since the graph is undirected, this is the node with a smaller ID of the edge endpoints.

GetDstNId()

Returns the ID of the destination node of the edge. Since the graph is undirected, this is the node with a greater ID of the edge endpoints.

TNGraph

class TNGraph

class TNGraph(Nodes, Edges)

class TNGraph(Graph)

Returns a new directed graph. If no parameters are provided, an empty graph is created. If Nodes and Edges are specified, space is preallocated for Nodes nodes and Edges edges. If Graph is specified, the new graph is a copy of the input graph.

Nodes have IDs, which are 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 an arbitrary node takes constant time and accessing any edge takes logarithmic time in the node degree.

TNGraph provides iterators for fast traversal of nodes and edges. Iterator classes are TNGraphNodeI for iterating over nodes and TNGraphEdgeI for iterating over edges.

TNGraph provides the following methods:

New()

Returns a pointer to a new graph.

New(Nodes, Edges)

Returns a pointer to a new graph and reserves enough memory for Nodes nodes and Edges edges.

Load(SIn)

Loads a graph from a binary stream SIn and returns a pointer to it.

Save(SOut)

Saves the graph to a binary stream SOut.

GetNodes()

Returns the number of nodes in the graph.

AddNode(NId)

Adds a node of ID NId to the graph, NId is an integer. Returns node ID. If NId is -1, node ID is automatically assigned. It throws an exception, if a node with ID NId already exists.

AddNode(NodeI)

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

DelNode(NId)

Deletes node of ID NId from the graph. NId is an integer. If the node of ID NId does not exist, the function throws an exception.

DelNode(NodeI)

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

IsNode(NId)

Returns true, if ID NId is a node in the graph.

BegNI()

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

EndNI()

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

GetNI(NId)

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

GetMxNId()

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

GetEdges()

Returns the number of edges in the graph.

AddEdge(SrcNId, DstNId)

Adds an edge from node SrcNId to node DstNId to the graph. Returns -1, if the edge was successfully added. Returns -2, if the edge already exists. The function throws an exception, if SrcNId or DstNId are not nodes in the graph.

AddEdge(EdgeI)

Adds an edge from EdgeI.GetSrcNId() to EdgeI.GetDstNId() to the graph. EdgeI is an edge iterator. Returns -1, if successful. Returns -2, otherwise.

DelEdge(SrcNId, DstNId)

Deletes an edge from node IDs SrcNId to DstNId from the graph. If the edge from SrcNId to DstNId does not exist in the graph, function still completes. But the function throws an exception, if SrcNId or DstNId are not nodes in the graph.

IsEdge(SrcNId, DstNId)

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

BegEI()

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

EndEI()

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

GetEI(SrcNId, DstNId)

Returns an edge iterator referring to edge between node IDs SrcNId and DstNId in the graph.

GetRndNId()

Returns an ID of a random node in the graph.

GetRndNI()

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

Empty()

Returns true if the graph is empty, has zero nodes.

Clr()

Deletes all nodes and edges from the graph.

Reserve(Nodes, Edges)

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

ReserveNIdInDeg(NId, Deg)

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

ReserveNIdOutDeg(NId, Deg)

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

HasFlag(Flag)

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

Defrag()

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

Dump(OutF=sys.stdout)

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

GetSmallGraph()

Returns a small graph on 5 nodes and 6 edges.

Below is some code demonstrating the use of the TNGraph class:

>>> G2 = snap.TNGraph.New()
>>> G2.AddNode(1)
1
>>> G2.AddNode(2)
2
>>> G2.AddNode(5)
5
>>> G2.AddEdge(1,5)
-1
>>> G2.AddEdge(1,2)
-1
>>> print G2.Empty()
False
>>> print G2.GetNodes()
3
>>> print G2.GetEdges()
2

TNGraphNodeI

class TNGraphNodeI

Returns a new node iterator for TNGraph. Normally, these objects are not created directly, but obtained via a call to the graph class TNGraph method, such as BegNI(), that returns a node iterator.

TNGraphNodeI provides the following methods:

Next()

Moves the iterator to the next node in the graph.

GetId()

Returns node ID of the current node.

GetDeg()

Returns degree of the current node, the sum of in-degree and out-degree.

GetInDeg()

Returns in-degree of the current node.

GetOutDeg()

Returns out-degree of the current node.

GetInNId(NodeN)

Returns ID of NodeN-th in-node (the node pointing to the current node).

GetOutNId(NodeN)

Returns ID of NodeN-th out-node (the node the current node points to).

GetNbrNId(NodeN)

Returns ID of NodeN-th neighboring node.

IsInNId(NId)

Tests whether node with ID NId points to the current node.

IsOutNId(NId)

Tests whether the current node points to node with ID NId.

IsNbrNId(NId)

Tests whether node with ID NId is a neighbor of the current node.

TNGraphEdgeI

class TNGraphEdgeI

Returns a new edge iterator for TNGraph. Normally, these objects are not created directly, but obtained via a call to the graph class TNGraph method, such as BegEI(), that returns an edge iterator.

TNGraphEdgeI provides the following methods:

Next()

Moves the iterator to the next edge in the graph.

GetId()

Always returns -1 for TNGraph, since edges do not have explicit IDs.

GetSrcNId()

Returns the ID of the source node of the edge.

GetDstNId()

Returns the ID of the destination node of the edge.

TNEANet

class TNEANet

class TNEANet(Nodes, Edges)

class TNEANet(Graph)

Returns a new directed multigraph with node and edge attributes. If no parameters are provided, an empty graph is created. If Nodes and Edges are specified, space is preallocated for Nodes nodes and Edges edges. If Graph is specified, the new graph is a copy of the input graph.

Nodes have IDs, which are arbitrary non-negative integers. Edges have IDs. There can be more than one directed edge from one source node to a destination node. Self loops (one per node) are allowed as well as multiple (parallel) edges. Nodes and edges can have attributes/data associated with them. The attributes can be added dynamically at runtime. The directed multigraph 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. The attributes are organized in a columnar store, where each attribute column is defined for all the nodes or edges in the network.

Methods for TNEANet are presented in two groups. The first group of methods deal with graph structure which includes nodes and edges. The second group of methods deal with node and edge attributes.

TNEANet provides iterators for fast traversal of nodes, edges and attributes. Iterator classes are TNEANetNodeI for iterating over nodes, TNEANetEdgeI for iterating over edges, and TNEANetAIntI, TNEANetAFltI, TNEANetAStrI for iterating over integer, float or string attributes, respectively. Attribute iterators can operate over attributes for nodes or edges.

TNEANet methods for graph structure are the following:

New()

Returns a pointer to a new graph.

New(Nodes, Edges)

Returns a pointer to a new graph and reserves enough memory for Nodes nodes and Edges edges.

Load(SIn)

Loads a graph from a binary stream SIn and returns a pointer to it.

Save(SOut)

Saves the graph to a binary stream SOut.

GetNodes()

Returns the number of nodes in the graph.

AddNode(NId)

Adds a node of ID NId to the graph, NId is an integer. Returns node ID. If NId is -1, node ID is automatically assigned. It throws an exception, if a node with ID NId already exists.

AddNode(NodeI)

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

DelNode(NId)

Deletes node of ID NId from the graph. NId is an integer. If the node of ID NId does not exist, the function throws an exception.

DelNode(NodeI)

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

IsNode(NId)

Returns true, if ID NId is a node in the graph.

BegNI()

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

EndNI()

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

GetNI(NId)

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

GetMxNId()

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

GetEdges()

Returns the number of edges in the graph.

AddEdge(SrcNId, DstNId, EId=-1)

Adds an edge with ID EId between node IDs SrcNId and DstNId to the graph. Returns the ID of the edge being added. If EId is -1, edge ID is automatically assigned. Throws an exception, if an edge with ID EId already exists or if either SrcNId or DstNId does not exist.

AddEdge(EdgeI)

Adds an edge from EdgeI.GetSrcNId() to EdgeI.GetDstNId() to the graph. EdgeI is an edge iterator. Returns the ID of the edge being added. If EId is -1, edge ID is automatically assigned. Throws an exception, if an edge with ID EId already exists or if either SrcNId or DstNId does not exist.

DelEdge(SrcNId, DstNId)

Deletes an edge from node IDs SrcNId to DstNId from the graph. If the edge from SrcNId to DstNId does not exist in the graph, function still completes. But the function throws an exception, if SrcNId or DstNId are not nodes in the graph.

IsEdge(SrcNId, DstNId)

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

BegEI()

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

EndEI()

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

GetEI(SrcNId, DstNId)

Returns an edge iterator referring to edge between node IDs SrcNId and DstNId in the graph.

GetRndNId()

Returns an ID of a random node in the graph.

GetRndNI()

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

Empty()

Returns true if the graph is empty, has zero nodes.

Clr()

Deletes all nodes and edges from the graph.

Reserve(Nodes, Edges)

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

ReserveNIdInDeg(NId, Deg)

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

ReserveNIdOutDeg(NId, Deg)

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

HasFlag(Flag)

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

Defrag()

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

Dump(OutF=sys.stdout)

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

GetSmallGraph()

Returns a small multigraph on 5 nodes and 6 edges.

TNEANet methods for node and edge attributes support attributes of different types. Integer, float and string attributes are implemented. Each attribute type has its own method for a particular task. Attributes are named via string names.

TNEANet methods for attributes are the following:

AddIntAttrN(Attr)

AddFltAttrN(Attr)

AddStrAttrN(Attr)

Defines a new integer, float or string node attribute, respectively.

AddIntAttrE(Attr)

AddFltAttrE(Attr)

AddStrAttrE(Attr)

Defines a new integer, float or string edge attribute, respectively.

DelAttrN(Attr)

Deletes node attribute Attr.

DelAttrE(Attr)

Deletes edge attribute Attr.

AddIntAttrDatN(NodeI, Value, Attr)

AddFltAttrDatN(NodeI, Value, Attr)

AddStrAttrDatN(NodeI, Value, Attr)

Sets the value of attribute named Attr for the node referred to by node iterator NodeI to Value. Value is an integer, a float, or a string, respectively.

AddIntAttrDatN(NId, Value, Attr)

AddFltAttrDatN(NId, Value, Attr)

AddStrAttrDatN(NId, Value, Attr)

Sets the value of attribute named Attr for the node with node id NId to Value. Value is an integer, a float, or a string, respectively.

AddIntAttrDatE(EdgeI, Value, Attr)

AddFltAttrDatE(EdgeI, Value, Attr)

AddStrAttrDatE(EdgeI, Value, Attr)

Sets the value of attribute named Attr for the edge referred to by edge iterator EdgeI to Value. Value is an integer, a float, or a string, respectively.

AddIntAttrDatE(EId, Value, Attr)

AddFltAttrDatE(EId, Value, Attr)

AddStrAttrDatE(EId, Value, Attr)

Sets the value of attribute named Attr for the edge with edge id EId to Value. Value is an integer, a float, or a string, respectively.

GetIntAttrDatN(NodeI, Attr)

GetFltAttrDatN(NodeI, Attr)

GetStrAttrDatN(NodeI, Attr)

Returns the value of attribute named Attr for the node referred to by node iterator NodeI*. Result is an integer, a float, or a string, respectively.

GetIntAttrDatN(NId, Attr)

GetFltAttrDatN(NId, Attr)

GetStrAttrDatN(NId, Attr)

Returns the value of attribute named Attr for the node with node id NId. Result is an integer, a float, or a string, respectively.

GetIntAttrDatE(EdgeI, Attr)

GetFltAttrDatE(EdgeI, Attr)

GetStrAttrDatE(EdgeI, Attr)

Returns the value of attribute named Attr for the edge referred to by edge iterator EdgeI*. Result is an integer, a float, or a string, respectively.

GetIntAttrDatE(EId, Attr)

GetFltAttrDatE(EId, Attr)

GetStrAttrDatE(EId, Attr)

Returns the value of attribute named Attr for the edge with edge id EId. Result is an integer, a float, or a string, respectively.

BegNAIntI(Attr)

BegNAFltI(Attr)

BegNAStrI(Attr)

Returns an integer, float, or string attribute iterator, respectively, of the attribute named Attr referring to the first node.

EndNAIntI(Attr)

EndNAFltI(Attr)

EndNAStrI(Attr)

Returns an integer, float, or string attribute iterator, respectively, of the attribute named Attr referring to the past-the-end node.

GetNAIntI(Attr, NId)

GetNAFltI(Attr, NId)

GetNAStrI(Attr, NId)

Returns an integer, float, or string attribute iterator, respectively, of the attribute named Attr referring to the node with node ID NId.

BegEAIntI(Attr)

BegEAFltI(Attr)

BegEAStrI(Attr)

Returns an integer, float, or string attribute iterator, respectively, of the attribute named Attr referring to the first edge.

EndEAIntI(Attr)

EndEAFltI(Attr)

EndEAStrI(Attr)

Returns an integer, float, or string attribute iterator, respectively, of the attribute named Attr referring to the past-the-end edge.

GetEAIntI(Attr, EId)

GetEAFltI(Attr, EId)

GetEAStrI(Attr, EId)

Returns an integer, float, or string attribute iterator, respectively, of the attribute named Attr referring to the edge with edge ID EId.

DelAttrDatN(NodeI, Attr)

Deletes the value of attribute named Attr for the node referred to by node iterator NodeI.

DelAttrDatN(NId, Attr)

Deletes the value of attribute named Attr for the node with node ID NId.

DelAttrDatE(EdgeI, Attr)

Deletes the value of attribute named Attr for the edge referred to by edge iterator EdgeI.

DelAttrDatE(EId, Attr)

Deletes the value of attribute named Attr for the edge with edge ID EId.

Below is some code demonstrating the use of the TNEANet class:

>>> G3 = snap.TNEANet.New()
>>> G3.AddNode(1)
1
>>> G3.AddNode(2)
2
>>> G3.AddNode(5)
5
>>> G3.AddEdge(1,5)
0
>>> G3.AddEdge(1,2)
1
>>> G3.AddEdge(1,2)
2
>>> print G3.Empty()
False
>>> print G3.GetNodes()
3
>>> print G3.GetEdges()
3

TNEANetNodeI

class TNEANetNodeI

Returns a new node iterator for TNEANet. Normally, these objects are not created directly, but obtained via a call to the network class TNEANet method, such as BegNI(), that returns a node iterator.

TNEANetNodeI provides the following methods:

Next()

Moves the iterator to the next node in the graph.

GetId()

Returns node ID of the current node.

GetDeg()

Returns degree of the current node, the sum of in-degree and out-degree.

GetInDeg()

Returns in-degree of the current node.

GetOutDeg()

Returns out-degree of the current node.

GetInNId(NodeN)

Returns ID of NodeN-th in-node (the node pointing to the current node).

GetOutNId(NodeN)

Returns ID of NodeN-th out-node (the node the current node points to).

GetNbrNId(NodeN)

Returns ID of NodeN-th neighboring node.

IsInNId(NId)

Tests whether node with ID NId points to the current node.

IsOutNId(NId)

Tests whether the current node points to node with ID NId.

IsNbrNId(NId)

Tests whether node with ID NId is a neighbor of the current node.

TNEANetEdgeI

class TNEANetEdgeI

Returns a new edge iterator for TNEANet. Normally, these objects are not created directly, but obtained via a call to the graph class TNEANet method, such as BegEI(), that returns an edge iterator.

TNEANetEdgeI provides the following methods:

Next()

Moves the iterator to the next edge in the graph.

GetId()

Always returns -1 for TNGraph, since edges do not have explicit IDs.

GetSrcNId()

Returns the ID of the source node of the edge.

GetDstNId()

Returns the ID of the destination node of the edge.

TNEANetAIntI, TNEANetAFltI, TNEANetAStrI

class TNEANetAIntI

class TNEANetAFltI

class TNEANetAStrI

Returns a new integer, float or string attribute iterator for TNEANet. Normally, these objects are not created directly, but obtained via a call to the graph class TNEANet method, such as BegNAIntI(), which returns an integer node iterator, or BegEAFltI(), which returns a float edge iterator.

Attribute iterators provide the following methods:

Next()

Moves the iterator to the next node or edge in the graph.

GetDat()

Returns an attribute of the node or edge.

IsDeleted()

Returns true if the attribute has been deleted.