bliss::Graph Class Reference

The class for undirected, vertex colored graphs. More...

#include <graph.hh>

Inheritance diagram for bliss::Graph:

Public Types
enum	SplittingHeuristic {   shs_f = 0, shs_fs, shs_fl, shs_fm,   shs_fsm, shs_flm }

Public Member Functions
	Graph (const unsigned int N=0)
	~Graph ()
void	write_dimacs (FILE *const fp)
void	write_dot (FILE *const fp)
void	write_dot (const char *const file_name)
bool	is_automorphism (const std::vector< unsigned int > &perm) const
virtual unsigned int	get_hash ()
unsigned int	get_nof_vertices () const
Graph *	permute (const unsigned int *const perm) const
unsigned int	add_vertex (const unsigned int color=0)
void	add_edge (const unsigned int v1, const unsigned int v2)
void	change_color (const unsigned int vertex, const unsigned int color)
int	cmp (Graph &other)
void	set_splitting_heuristic (const SplittingHeuristic shs)
Public Member Functions inherited from bliss::AbstractGraph
void	set_verbose_level (const unsigned int level)
void	set_verbose_file (FILE *const fp)
void	set_failure_recording (const bool active)
void	set_component_recursion (const bool active)
void	find_automorphisms (Stats &stats, void(*hook)(void *user_param, unsigned int n, const unsigned int *aut), void *hook_user_param)
const unsigned int *	canonical_form (Stats &stats, void(*hook)(void *user_param, unsigned int n, const unsigned int *aut), void *hook_user_param)
void	set_long_prune_activity (const bool active)

Static Public Member Functions
static Graph *	read_dimacs (FILE *const fp, FILE *const errstr=stderr)

Additional Inherited Members
Protected Attributes inherited from bliss::AbstractGraph
unsigned int	cr_level

Detailed Description

The class for undirected, vertex colored graphs.

Multiple edges between vertices are not allowed (i.e., are ignored).

Member Enumeration Documentation

enum bliss::Graph::SplittingHeuristic

The possible splitting heuristics. The selected splitting heuristics affects the computed canonical labelings; therefore, if you want to compare whether two graphs are isomorphic by computing and comparing (for equality) their canonical versions, be sure to use the same splitting heuristics for both graphs.

Enumerator:

shs_f	First non-unit cell. Very fast but may result in large search spaces on difficult graphs. Use for large but easy graphs.
shs_fs	First smallest non-unit cell. Fast, should usually produce smaller search spaces than shs_f.
shs_fl	First largest non-unit cell. Fast, should usually produce smaller search spaces than shs_f.
shs_fm	First maximally non-trivially connected non-unit cell. Not so fast, should usually produce smaller search spaces than shs_f, shs_fs, and shs_fl.
shs_fsm	First smallest maximally non-trivially connected non-unit cell. Not so fast, should usually produce smaller search spaces than shs_f, shs_fs, and shs_fl.
shs_flm	First largest maximally non-trivially connected non-unit cell. Not so fast, should usually produce smaller search spaces than shs_f, shs_fs, and shs_fl.

Constructor & Destructor Documentation

bliss::Graph::Graph

(

const unsigned int

N = 0

)

Create a new graph with N vertices and no edges.

bliss::Graph::~Graph

(

)

Destroy the graph.

Member Function Documentation

void bliss::Graph::add_edge	(	const unsigned int	v1,
		const unsigned int	v2
	)

Add an edge between vertices v1 and v2. Duplicate edges between vertices are ignored but try to avoid introducing them in the first place as they are not ignored immediately but will consume memory and computation resources for a while.

unsigned int bliss::Graph::add_vertex

(

const unsigned int

color = 0

)

Add a new vertex with color color in the graph and return its index.

void bliss::Graph::change_color	(	const unsigned int	vertex,
		const unsigned int	color
	)

Change the color of the vertex vertex to color.

int bliss::Graph::cmp

(

Graph &

other

)

Compare this graph with the graph other. Returns 0 if the graphs are equal, and a negative (positive) integer if this graph is "smaller than" ("greater than", resp.) than other.

unsigned int bliss::Graph::get_hash ( )

virtual

Get a hash value for the graph.

Returns

the hash value

Implements bliss::AbstractGraph.

unsigned int bliss::Graph::get_nof_vertices ( ) const

inlinevirtual

Return the number of vertices in the graph.

Implements bliss::AbstractGraph.

bool bliss::Graph::is_automorphism ( const std::vector< unsigned int > &  perm ) const

virtual

Check whether perm is an automorphism of this graph. Unoptimized, mainly for debugging purposes.

Reimplemented from bliss::AbstractGraph.

Graph * bliss::Graph::permute ( const unsigned int *const  perm ) const

virtual

Return a new graph that is the result of applying the permutation perm to this graph. This graph is not modified. perm must contain N=this.get_nof_vertices() elements and be a bijection on {0,1,...,N-1}, otherwise the result is undefined or a segfault.

Implements bliss::AbstractGraph.

Graph * bliss::Graph::read_dimacs ( FILE *const  fp, FILE *const  errstr = stderr  )

static

Read the graph from the file fp in a variant of the DIMACS format. See the bliss website for the definition of the file format. Note that in the DIMACS file the vertices are numbered from 1 to N while in this C++ API they are from 0 to N-1. Thus the vertex n in the file corresponds to the vertex n-1 in the API.

Parameters

fp	the file stream for the graph file
errstr	if non-null, the possible error messages are printed in this file stream

Returns

a new Graph object or 0 if reading failed for some reason

void bliss::Graph::set_splitting_heuristic ( const SplittingHeuristic  shs )

inline

Set the splitting heuristic used by the automorphism and canonical labeling algorithm. The selected splitting heuristics affects the computed canonical labelings; therefore, if you want to compare whether two graphs are isomorphic by computing and comparing (for equality) their canonical versions, be sure to use the same splitting heuristics for both graphs.

void bliss::Graph::write_dimacs ( FILE *const  fp )

virtual

Write the graph to a file in a variant of the DIMACS format. See the bliss website for the definition of the file format.

Implements bliss::AbstractGraph.

void bliss::Graph::write_dot ( FILE *const  fp )

virtual

Write the graph to a file in the graphviz dotty format.

Parameters

fp	the file stream where the graph is written

Implements bliss::AbstractGraph.

void bliss::Graph::write_dot ( const char *const  file_name )

virtual

Write the graph in a file in the graphviz dotty format. Do nothing if the file cannot be written.

Parameters

file_name

the name of the file to which the graph is written

Implements bliss::AbstractGraph.

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

• graph.hh
• graph.cc