Interface for graph tools

This file contains definitions and functions related to graphs and designs.

Copyright: See COPYING file that comes with this distribution

Enums

enum matrix_isomorphism_t

Isomorphism types for matrices

Isotopy: permute rows, columns and symbols Matrix isomorphism: permute rows and columns Conference isomorphism: permute rows, columns and to row and column negations (values in 0, +1, -1) Orthogonal array isomorphism: permutations of rows, columns and column symbol permutations

Values:

enumerator ISOTOPY: isotopy: permute rows, columns and symbols

enumerator MATRIX_ISOMORPHISM: permute rows and columns

enumerator CONFERENCE_ISOMORPHISM: permute rows, columns and to row and column negations (values in 0, +1, -1)

enumerator OA_ISOMORPHISM: permutations of rows, columns and column symbol permutations

Functions

array_link transformGraph(const array_link &graph, const std::vector<int> vertex_permutation, int verbose = 1): Apply a vertex permutation to a graph.

array_transformation_t reduceOAnauty(const array_link &array, int verbose = 0): Reduce an orthogonal array to Nauty minimal form. the array transformation is returned.

array_transformation_t reduceOAnauty(const array_link &array, int verbose, const arraydata_t &arrayclass): Reduce an orthogonal array to Nauty minimal form. the array transformation is returned.

std::pair<array_link, std::vector<int>> array2graph(const array_link &array, int verbose = 1)

Convert orthogonal array to graph representation

The conversion method is as in Ryan and Bulutoglu. The resulting graph is bi-partite. The graph representation can be used for isomorphism testing.

std::pair<array_link, std::vector<int>> array2graph(const array_link &array, int verbose, const arraydata_t &arrayclass)

Convert orthogonal array to graph representation

The conversion method is as in Ryan and Bulutoglu. The resulting graph is bi-partite. The graph representation can be used for isomorphism testing.

array_transformation_t oagraph2transformation(const std::vector<int> &pp, const arraydata_t &arrayclass, int verbose = 1): From a relabelling of the graph return the corresponding array transformation.

Variables

const matrix_isomorphism_t CONFERENCE_RESTRICTED_ISOMORPHISM = OA_ISOMORPHISM : isomorphism type for column and row permtations and column permutations

namespace nauty

Functions

std::vector<int> reduceNauty(const array_link &graph, std::vector<int> colors, int verbose = 0)

Reduce a colored graph to Nauty minimal form

The transformation returned is from the normal form to the specified graph.

Parameters:

graph – Graph in incidence matrix form
colors – Colors of the graph nodes
verbose – Verbosity level

Returns:

Relabelling of the graph vertices