Detailed Description

graph structure with common algorithms for directed and undirected graphs

Functions
SCIP_RETCODE	SCIPdigraphCreate (SCIP_DIGRAPH **digraph, int nnodes)

SCIP_RETCODE	SCIPdigraphResize (SCIP_DIGRAPH *digraph, int nnodes)

SCIP_RETCODE	SCIPdigraphCopy (SCIP_DIGRAPH *targetdigraph, SCIP_DIGRAPH sourcedigraph)

SCIP_RETCODE	SCIPdigraphSetSizes (SCIP_DIGRAPH digraph, int sizes)

void	SCIPdigraphFree (SCIP_DIGRAPH **digraph)

SCIP_RETCODE	SCIPdigraphAddArc (SCIP_DIGRAPH digraph, int startnode, int endnode, void data)

SCIP_RETCODE	SCIPdigraphAddArcSafe (SCIP_DIGRAPH digraph, int startnode, int endnode, void data)

SCIP_RETCODE	SCIPdigraphSetNSuccessors (SCIP_DIGRAPH *digraph, int node, int nsuccessors)

int	SCIPdigraphGetNNodes (SCIP_DIGRAPH *digraph)

void *	SCIPdigraphGetNodeData (SCIP_DIGRAPH *digraph, int node)

void	SCIPdigraphSetNodeData (SCIP_DIGRAPH digraph, void dataptr, int node)

int	SCIPdigraphGetNArcs (SCIP_DIGRAPH *digraph)

int	SCIPdigraphGetNSuccessors (SCIP_DIGRAPH *digraph, int node)

int *	SCIPdigraphGetSuccessors (SCIP_DIGRAPH *digraph, int node)

void **	SCIPdigraphGetSuccessorsData (SCIP_DIGRAPH *digraph, int node)

SCIP_RETCODE	SCIPdigraphComputeUndirectedComponents (SCIP_DIGRAPH digraph, int minsize, int components, int *ncomponents)

SCIP_RETCODE	SCIPdigraphComputeDirectedComponents (SCIP_DIGRAPH digraph, int compidx, int strongcomponents, int strongcompstartidx, int nstrongcomponents)

SCIP_RETCODE	SCIPdigraphTopoSortComponents (SCIP_DIGRAPH *digraph)

int	SCIPdigraphGetNComponents (SCIP_DIGRAPH *digraph)

void	SCIPdigraphGetComponent (SCIP_DIGRAPH digraph, int compidx, int nodes, int nnodes)

void	SCIPdigraphFreeComponents (SCIP_DIGRAPH *digraph)

void	SCIPdigraphPrint (SCIP_DIGRAPH digraph, SCIP_MESSAGEHDLR messagehdlr, FILE *file)

void	SCIPdigraphPrintGml (SCIP_DIGRAPH digraph, FILE file)

void	SCIPdigraphPrintComponents (SCIP_DIGRAPH digraph, SCIP_MESSAGEHDLR messagehdlr, FILE *file)

Function Documentation

◆ SCIPdigraphCreate()

SCIP_RETCODE SCIPdigraphCreate	(	SCIP_DIGRAPH **	digraph,
		int	nnodes
	)

creates directed graph structure

Parameters

digraph	pointer to store the created directed graph
nnodes	number of nodes

Definition at line 6443 of file misc.c.

References BMSallocClearMemoryArray, BMSallocMemory, nnodes, NULL, SCIP_ALLOC, and SCIP_OKAY.

Referenced by addBranchingComplementaritiesSOS1(), enforceConflictgraph(), findComponents(), initConflictgraph(), initImplGraphSOS1(), presolRoundConssSOS1(), presolRoundVarsSOS1(), SCIPcliquetableComputeCliqueComponents(), sortGenVBounds(), and tightenVarsBoundsSOS1().

◆ SCIPdigraphResize()

SCIP_RETCODE SCIPdigraphResize	(	SCIP_DIGRAPH *	digraph,
		int	nnodes
	)

resize directed graph structure

Parameters

digraph	directed graph
nnodes	new number of nodes

Definition at line 6472 of file misc.c.

References SCIP_Digraph::arcdata, BMSreallocMemoryArray, nnodes, SCIP_Digraph::nnodes, SCIP_Digraph::nodedata, SCIP_Digraph::nsuccessors, NULL, SCIP_ALLOC, SCIP_OKAY, SCIP_Digraph::successors, and SCIP_Digraph::successorssize.

◆ SCIPdigraphCopy()

SCIP_RETCODE SCIPdigraphCopy	(	SCIP_DIGRAPH **	targetdigraph,
		SCIP_DIGRAPH *	sourcedigraph
	)

copies directed graph structure

Note: The data in nodedata is copied verbatim. This possibly has to be adapted by the user.

Parameters

targetdigraph	pointer to store the copied directed graph
sourcedigraph	source directed graph

Definition at line 6508 of file misc.c.

References SCIP_Digraph::arcdata, BMSallocClearMemoryArray, BMSallocMemory, BMSduplicateMemoryArray, SCIP_Digraph::components, SCIP_Digraph::componentstarts, SCIP_Digraph::ncomponents, nnodes, SCIP_Digraph::nnodes, SCIP_Digraph::nodedata, SCIP_Digraph::nsuccessors, NULL, SCIP_ALLOC, SCIP_OKAY, and SCIP_Digraph::successors.

◆ SCIPdigraphSetSizes()

SCIP_RETCODE SCIPdigraphSetSizes	(	SCIP_DIGRAPH *	digraph,
		int *	sizes
	)

sets the sizes of the successor lists for the nodes in a directed graph and allocates memory for the lists

Parameters

digraph	directed graph
sizes	sizes of the successor lists

Definition at line 6567 of file misc.c.

References SCIP_Digraph::arcdata, BMSallocMemoryArray, SCIP_Digraph::nnodes, SCIP_Digraph::nsuccessors, NULL, SCIP_ALLOC, SCIP_OKAY, SCIP_Digraph::successors, and SCIP_Digraph::successorssize.

Referenced by findComponents(), and SCIPcliquetableComputeCliqueComponents().

◆ SCIPdigraphFree()

void SCIPdigraphFree ( SCIP_DIGRAPH ** digraph )

frees given directed graph structure

Parameters

digraph pointer to the directed graph

Definition at line 6589 of file misc.c.

References BMSfreeMemory, BMSfreeMemoryArray, BMSfreeMemoryArrayNull, NULL, and SCIPdigraphFreeComponents().

Referenced by findComponents(), freeConflictgraph(), presolRoundConssSOS1(), presolRoundVarsSOS1(), SCIPcliquetableComputeCliqueComponents(), sortGenVBounds(), and tightenVarsBoundsSOS1().

◆ SCIPdigraphAddArc()

SCIP_RETCODE SCIPdigraphAddArc	(	SCIP_DIGRAPH *	digraph,
		int	startnode,
		int	endnode,
		void *	data
	)

add (directed) arc and a related data to the directed graph structure

Note: if the arc is already contained, it is added a second time

Parameters

digraph	directed graph
startnode	start node of the arc
endnode	start node of the arc
data	data that should be stored for the arc; or NULL

Definition at line 6666 of file misc.c.

References SCIP_Digraph::arcdata, ensureSuccessorsSize(), nnodes, SCIP_Digraph::nsuccessors, NULL, SCIP_CALL, SCIP_OKAY, and SCIP_Digraph::successors.

Referenced by addBranchingComplementaritiesSOS1(), fillDigraph(), SCIPcliquetableComputeCliqueComponents(), SCIPdigraphComputeUndirectedComponents(), sortGenVBounds(), and updateArcData().

◆ SCIPdigraphAddArcSafe()

SCIP_RETCODE SCIPdigraphAddArcSafe	(	SCIP_DIGRAPH *	digraph,
		int	startnode,
		int	endnode,
		void *	data
	)

add (directed) arc to the directed graph structure, if it is not contained, yet

Note: if there already exists an arc from startnode to endnode, the new arc is not added, even if its data is different

Parameters

digraph	directed graph
startnode	start node of the arc
endnode	start node of the arc
data	data that should be stored for the arc; or NULL

Definition at line 6694 of file misc.c.

References SCIP_Digraph::arcdata, ensureSuccessorsSize(), nnodes, SCIP_Digraph::nsuccessors, NULL, SCIP_CALL, SCIP_OKAY, and SCIP_Digraph::successors.

Referenced by enforceConflictgraph(), extensionOperatorSOS1(), genConflictgraphLinearCons(), handleNewVariableSOS1(), initConflictgraph(), performImplicationGraphAnalysis(), and presolRoundConssSOS1().

◆ SCIPdigraphSetNSuccessors()

SCIP_RETCODE SCIPdigraphSetNSuccessors	(	SCIP_DIGRAPH *	digraph,
		int	node,
		int	nsuccessors
	)

sets the number of successors to a given value

Parameters

digraph	directed graph
node	node for which the number of successors has to be changed
nsuccessors	new number of successors

Definition at line 6728 of file misc.c.

References nnodes, SCIP_Digraph::nsuccessors, NULL, and SCIP_OKAY.

Referenced by resetConflictgraphSOS1().

◆ SCIPdigraphGetNNodes()

int SCIPdigraphGetNNodes ( SCIP_DIGRAPH * digraph )

returns the number of nodes of the given digraph

Parameters

digraph directed graph

Definition at line 6744 of file misc.c.

References SCIP_Digraph::nnodes, and NULL.

Referenced by cliqueGetCommonSuccessorsSOS1(), nodeGetSolvalBinaryBigMSOS1(), nodeGetSolvalVarboundLbSOS1(), nodeGetSolvalVarboundUbSOS1(), performImplicationGraphAnalysis(), and sortGenVBounds().

◆ SCIPdigraphGetNodeData()

void* SCIPdigraphGetNodeData	(	SCIP_DIGRAPH *	digraph,
		int	node
	)

returns the node data, or NULL if no data exist

Parameters

digraph	directed graph
node	node for which the node data is returned

Definition at line 6754 of file misc.c.

References nnodes, SCIP_Digraph::nodedata, and NULL.

Referenced by addBranchingComplementaritiesSOS1(), checkConComponentsVarbound(), detectVarboundSOS1(), freeConflictgraph(), generateBoundInequalityFromSOS1Nodes(), getBoundConsFromVertices(), nodeGetSolvalVarboundLbSOS1(), nodeGetSolvalVarboundUbSOS1(), passConComponentVarbound(), propVariableNonzero(), and sepaImplBoundCutsSOS1().

◆ SCIPdigraphSetNodeData()

void SCIPdigraphSetNodeData	(	SCIP_DIGRAPH *	digraph,
		void *	dataptr,
		int	node
	)

sets the node data

Note: The old user pointer is not freed. This has to be done by the user

Parameters

digraph	directed graph
dataptr	user node data pointer, or NULL
node	node for which the node data is returned

Definition at line 6770 of file misc.c.

References nnodes, SCIP_Digraph::nodedata, and NULL.

Referenced by freeConflictgraph(), initConflictgraph(), and initImplGraphSOS1().

◆ SCIPdigraphGetNArcs()

int SCIPdigraphGetNArcs ( SCIP_DIGRAPH * digraph )

returns the total number of arcs in the given digraph

Parameters

digraph directed graph

Definition at line 6784 of file misc.c.

References narcs, SCIP_Digraph::nnodes, SCIP_Digraph::nsuccessors, and NULL.

Referenced by SCIP_DECL_SEPAEXECLP(), and sepaImplBoundCutsSOS1().

◆ SCIPdigraphGetNSuccessors()

int SCIPdigraphGetNSuccessors	(	SCIP_DIGRAPH *	digraph,
		int	node
	)

returns the number of successor nodes of the given node

Parameters

digraph	directed graph
node	node for which the number of outgoing arcs is returned

Definition at line 6802 of file misc.c.

References nnodes, SCIP_Digraph::nsuccessors, NULL, and SCIP_Digraph::successorssize.

Referenced by addBranchingComplementaritiesSOS1(), checkConComponentsVarbound(), checkSwitchNonoverlappingSOS1Methods(), cliqueGetCommonSuccessorsSOS1(), computeVarsCoverSOS1(), enforceConflictgraph(), genConflictgraphLinearCons(), getBoundConsFromVertices(), getBranchingPrioritiesSOS1(), getBranchingVerticesSOS1(), getCoverVertices(), getDiveBdChgsSOS1conflictgraph(), getSOS1Implications(), getVectorOfWeights(), handleNewVariableSOS1(), initConflictgraph(), initImplGraphSOS1(), initTCliquegraph(), isConnectedSOS1(), isViolatedSOS1(), markNeighborsMWISHeuristic(), maxWeightIndSetHeuristic(), passConComponentVarbound(), performImplicationGraphAnalysis(), presolRoundConssSOS1(), presolRoundVarsSOS1(), propVariableNonzero(), resetConflictgraphSOS1(), SCIP_DECL_SEPAEXECLP(), sepaImplBoundCutsSOS1(), tightenVarsBoundsSOS1(), and updateArcData().

◆ SCIPdigraphGetSuccessors()

int* SCIPdigraphGetSuccessors	(	SCIP_DIGRAPH *	digraph,
		int	node
	)

returns the array of indices of the successor nodes; this array must not be changed from outside

Parameters

digraph	directed graph
node	node for which the array of outgoing arcs is returned

Definition at line 6817 of file misc.c.

References nnodes, SCIP_Digraph::nsuccessors, NULL, SCIP_Digraph::successors, and SCIP_Digraph::successorssize.

Referenced by addBranchingComplementaritiesSOS1(), checkConComponentsVarbound(), cliqueGetCommonSuccessorsSOS1(), computeVarsCoverSOS1(), enforceConflictgraph(), genConflictgraphLinearCons(), getBoundConsFromVertices(), getBranchingVerticesSOS1(), getCoverVertices(), getDiveBdChgsSOS1conflictgraph(), getSOS1Implications(), getVectorOfWeights(), handleNewVariableSOS1(), initConflictgraph(), initImplGraphSOS1(), initTCliquegraph(), isConnectedSOS1(), isViolatedSOS1(), markNeighborsMWISHeuristic(), passConComponentVarbound(), performImplicationGraphAnalysis(), presolRoundConssSOS1(), propVariableNonzero(), resetConflictgraphSOS1(), SCIP_DECL_SEPAEXECLP(), sepaImplBoundCutsSOS1(), tightenVarsBoundsSOS1(), and updateArcData().

◆ SCIPdigraphGetSuccessorsData()

void** SCIPdigraphGetSuccessorsData	(	SCIP_DIGRAPH *	digraph,
		int	node
	)

returns the array of data corresponding to the arcs originating at the given node, or NULL if no data exist; this array must not be changed from outside

Parameters

digraph	directed graph
node	node for which the data corresponding to the outgoing arcs is returned

Definition at line 6835 of file misc.c.

References SCIP_Digraph::arcdata, nnodes, SCIP_Digraph::nsuccessors, NULL, and SCIP_Digraph::successorssize.

Referenced by getSOS1Implications(), performImplicationGraphAnalysis(), presolRoundVarsSOS1(), propVariableNonzero(), sepaImplBoundCutsSOS1(), and updateArcData().

◆ SCIPdigraphComputeUndirectedComponents()

SCIP_RETCODE SCIPdigraphComputeUndirectedComponents	(	SCIP_DIGRAPH *	digraph,
		int	minsize,
		int *	components,
		int *	ncomponents
	)

Compute undirected connected components on the given graph.

Note: For each arc, its reverse is added, so the graph does not need to be the directed representation of an undirected graph.

Parameters

digraph	directed graph
minsize	all components with less nodes are ignored
components	array with as many slots as there are nodes in the directed graph to store for each node the component to which it belongs (components are numbered 0 to ncomponents - 1); or NULL, if components are accessed one-by-one using SCIPdigraphGetComponent()
ncomponents	pointer to store the number of components; or NULL, if the number of components is accessed by SCIPdigraphGetNComponents()

Definition at line 6929 of file misc.c.

References BMSallocClearMemoryArray, BMSallocMemoryArray, BMSclearMemoryArray, BMScopyMemoryArray, BMSfreeMemoryArrayNull, BMSreallocMemoryArray, SCIP_Digraph::components, SCIP_Digraph::componentstarts, SCIP_Digraph::componentstartsize, depthFirstSearch(), SCIP_Digraph::ncomponents, SCIP_Digraph::nnodes, SCIP_Digraph::nsuccessors, NULL, SCIP_ALLOC_TERMINATE, SCIP_Bool, SCIP_CALL_TERMINATE, SCIP_OKAY, SCIPdigraphAddArc(), SCIPdigraphFreeComponents(), and SCIP_Digraph::successors.

Referenced by findComponents(), SCIPcliquetableComputeCliqueComponents(), and sortGenVBounds().

◆ SCIPdigraphComputeDirectedComponents()

SCIP_RETCODE SCIPdigraphComputeDirectedComponents	(	SCIP_DIGRAPH *	digraph,
		int	compidx,
		int *	strongcomponents,
		int *	strongcompstartidx,
		int *	nstrongcomponents
	)

Computes all strongly connected components of an undirected connected component with Tarjan's Algorithm. The resulting strongly connected components are sorted topologically (starting from the end of the strongcomponents array).

Note: In general a topological sort of the strongly connected components is not unique.

Parameters

digraph	directed graph
compidx	number of the undirected connected component
strongcomponents	array to store the strongly connected components (length >= size of the component)
strongcompstartidx	array to store the start indices of the strongly connected components (length >= size of the component)
nstrongcomponents	pointer to store the number of strongly connected components

Definition at line 7258 of file misc.c.

References BMSallocMemoryArray, BMSfreeMemoryArrayNull, SCIP_Digraph::components, SCIP_Digraph::componentstarts, FALSE, nnodes, SCIP_Digraph::nnodes, NULL, SCIP_ALLOC_TERMINATE, SCIP_Bool, SCIP_OKAY, SCIPdebugMessage, tarjan(), and TRUE.

Referenced by sortGenVBounds().

◆ SCIPdigraphTopoSortComponents()

SCIP_RETCODE SCIPdigraphTopoSortComponents ( SCIP_DIGRAPH * digraph )

Performes an (almost) topological sort on the undirected components of the given directed graph. The undirected components should be computed before using SCIPdigraphComputeUndirectedComponents().

Note: In general a topological sort is not unique. Note, that there might be directed cycles, that are randomly broken, which is the reason for having only almost topologically sorted arrays.

Performs an (almost) topological sort on the undirected components of the given directed graph. The undirected components should be computed before using SCIPdigraphComputeUndirectedComponents().

Note: In general a topological sort is not unique. Note, that there might be directed cycles, that are randomly broken, which is the reason for having only almost topologically sorted arrays.

Parameters

digraph directed graph

Definition at line 7049 of file misc.c.

References BMSallocClearMemoryArray, BMSallocMemoryArray, BMSfreeMemoryArray, SCIP_Digraph::components, SCIP_Digraph::componentstarts, depthFirstSearch(), SCIP_Digraph::ncomponents, SCIP_Digraph::nnodes, NULL, SCIP_ALLOC, SCIP_Bool, and SCIP_OKAY.

Referenced by sortGenVBounds().

◆ SCIPdigraphGetNComponents()

int SCIPdigraphGetNComponents ( SCIP_DIGRAPH * digraph )

returns the number of previously computed undirected components for the given directed graph

Parameters

digraph directed graph

Definition at line 7113 of file misc.c.

References SCIP_Digraph::componentstartsize, SCIP_Digraph::ncomponents, and NULL.

Referenced by sortComponents(), and sortGenVBounds().

◆ SCIPdigraphGetComponent()

void SCIPdigraphGetComponent	(	SCIP_DIGRAPH *	digraph,
		int	compidx,
		int **	nodes,
		int *	nnodes
	)

Returns the previously computed undirected component of the given number for the given directed graph. If the components were sorted using SCIPdigraphTopoSortComponents(), the component is (almost) topologically sorted.

Parameters

digraph	directed graph
compidx	number of the component to return
nodes	pointer to store the nodes in the component; or NULL, if not needed
nnodes	pointer to store the number of nodes in the component; or NULL, if not needed

Definition at line 7126 of file misc.c.

References SCIP_Digraph::components, SCIP_Digraph::componentstarts, and NULL.

Referenced by sortComponents(), and sortGenVBounds().

◆ SCIPdigraphFreeComponents()

void SCIPdigraphFreeComponents ( SCIP_DIGRAPH * digraph )

frees the component information for the given directed graph

Parameters

digraph directed graph

Definition at line 7347 of file misc.c.

References BMSfreeMemoryArray, SCIP_Digraph::components, SCIP_Digraph::componentstarts, SCIP_Digraph::componentstartsize, SCIP_Digraph::ncomponents, and NULL.

Referenced by SCIPdigraphComputeUndirectedComponents(), and SCIPdigraphFree().

◆ SCIPdigraphPrint()

void SCIPdigraphPrint	(	SCIP_DIGRAPH *	digraph,
		SCIP_MESSAGEHDLR *	messagehdlr,
		FILE *	file
	)

output of the given directed graph via the given message handler

Parameters

digraph	directed graph
messagehdlr	message handler
file	output file (or NULL for standard output)

Definition at line 7374 of file misc.c.

References SCIP_Digraph::nnodes, SCIP_Digraph::nsuccessors, SCIPmessageFPrintInfo(), and SCIP_Digraph::successors.

◆ SCIPdigraphPrintGml()

void SCIPdigraphPrintGml	(	SCIP_DIGRAPH *	digraph,
		FILE *	file
	)

prints the given directed graph structure in GML format into the given file

Parameters

digraph	directed graph
file	file to write to

Definition at line 7409 of file misc.c.

References SCIP_Digraph::nnodes, SCIP_Digraph::nsuccessors, NULL, SCIP_MAXSTRLEN, SCIPgmlWriteArc(), SCIPgmlWriteClosing(), SCIPgmlWriteNode(), SCIPgmlWriteOpening(), SCIPsnprintf(), SCIP_Digraph::successors, and TRUE.

◆ SCIPdigraphPrintComponents()

void SCIPdigraphPrintComponents	(	SCIP_DIGRAPH *	digraph,
		SCIP_MESSAGEHDLR *	messagehdlr,
		FILE *	file
	)

output of the given directed graph via the given message handler

Parameters

digraph	directed graph
messagehdlr	message handler
file	output file (or NULL for standard output)

Definition at line 7448 of file misc.c.

References SCIP_Digraph::components, SCIP_Digraph::componentstarts, SCIP_Digraph::ncomponents, and SCIPmessageFPrintInfo().

SCIP

Detailed Description

Functions

Function Documentation

◆ SCIPdigraphCreate()

◆ SCIPdigraphResize()

◆ SCIPdigraphCopy()

◆ SCIPdigraphSetSizes()

◆ SCIPdigraphFree()

◆ SCIPdigraphAddArc()

◆ SCIPdigraphAddArcSafe()

◆ SCIPdigraphSetNSuccessors()

◆ SCIPdigraphGetNNodes()

◆ SCIPdigraphGetNodeData()

◆ SCIPdigraphSetNodeData()

◆ SCIPdigraphGetNArcs()

◆ SCIPdigraphGetNSuccessors()

◆ SCIPdigraphGetSuccessors()

◆ SCIPdigraphGetSuccessorsData()

◆ SCIPdigraphComputeUndirectedComponents()

◆ SCIPdigraphComputeDirectedComponents()

◆ SCIPdigraphTopoSortComponents()

◆ SCIPdigraphGetNComponents()

◆ SCIPdigraphGetComponent()

◆ SCIPdigraphFreeComponents()

◆ SCIPdigraphPrint()

◆ SCIPdigraphPrintGml()

◆ SCIPdigraphPrintComponents()