Parameters for Seymour decomposition algorithm. More...

#include <seymour.h>

Public Attributes
bool	stopWhenIrregular
	Whether to stop decomposing once irregularity is determined.

bool	stopWhenNongraphic
	Whether to stop decomposing once non-graphicness (or being non-network) is determined.

bool	stopWhenNoncographic
	Whether to stop decomposing once non-cographicness (or being non-conetwork) is determined.

bool	stopWhenNeitherGraphicNorCoGraphic
	Whether to stop decomposing once non-graphicness and non-cographicness (or not being network and not being conetwork) is determined.

bool	seriesParallel
	Whether to allow series-parallel operations in the decomposition tree; default: `true`.

bool	planarityCheck
	Whether minors identified as graphic should still be checked for cographicness; default: `false`.

bool	directGraphicness
	Whether to use fast graphicness routines; default: `true`.

bool	preferGraphicness
	Whether to first test for (co)graphicness (or being (co)network) before applying series-parallel reductions.

int	decomposeStrategy
	How to deal with 3-separations.

bool	constructLeafGraphs
	Whether to construct (co)graphs for all leaf nodes that are (co)graphic or (co)network.

bool	constructAllGraphs
	Whether to construct (co)graphs for all nodes that are (co)graphic or (co)network.

Detailed Description

Parameters for Seymour decomposition algorithm.

Member Data Documentation

◆ constructAllGraphs

bool CMR_SEYMOUR_PARAMS::constructAllGraphs

Whether to construct (co)graphs for all nodes that are (co)graphic or (co)network.

◆ constructLeafGraphs

bool CMR_SEYMOUR_PARAMS::constructLeafGraphs

Whether to construct (co)graphs for all leaf nodes that are (co)graphic or (co)network.

◆ decomposeStrategy

int CMR_SEYMOUR_PARAMS::decomposeStrategy

How to deal with 3-separations.

The value is a bit-wise OR of two decisions, one per rank distribution:

CMR_SEYMOUR_DECOMPOSE_FLAG_DISTRIBUTED_MASK indicates what to do if ranks are 1 and 1.
CMR_SEYMOUR_DECOMPOSE_FLAG_CONCENTRATED_MASK indicates what to do if ranks are 2 and 0.

The possible choices for distributed ranks (1 and 1) are:

CMR_SEYMOUR_DECOMPOSE_FLAG_DISTRIBUTED_PIVOT pivot such that the rank distribution becomes concentrated.
CMR_SEYMOUR_DECOMPOSE_FLAG_DISTRIBUTED_DELTASUM for the \( \Delta \)-sum (default).
CMR_SEYMOUR_DECOMPOSE_FLAG_DISTRIBUTED_YSUM for the Y-sum.

The possible choices for concentrated ranks (2 and 0) are:

CMR_SEYMOUR_DECOMPOSE_FLAG_CONCENTRATED_PIVOT pivot such that the rank distribution becomes distributed.
CMR_SEYMOUR_DECOMPOSE_FLAG_CONCENTRATED_THREESUM for the 3-sum (default).

See also: Decomposition of regular matroids for a description of these sums.

A decomposition as described by Seymour can be selected via CMR_SEYMOUR_DECOMPOSE_FLAG_SEYMOUR. A decomposition as used by Truemper can be selected via CMR_SEYMOUR_DECOMPOSE_FLAG_TRUEMPER. The default is to not carry out any pivots and choose Seymour's or Truemper's definition depending on the rank distribution.

◆ directGraphicness

bool CMR_SEYMOUR_PARAMS::directGraphicness

Whether to use fast graphicness routines; default: true.

◆ planarityCheck

bool CMR_SEYMOUR_PARAMS::planarityCheck

Whether minors identified as graphic should still be checked for cographicness; default: false.

◆ preferGraphicness

bool CMR_SEYMOUR_PARAMS::preferGraphicness

Whether to first test for (co)graphicness (or being (co)network) before applying series-parallel reductions.

◆ seriesParallel

bool CMR_SEYMOUR_PARAMS::seriesParallel

Whether to allow series-parallel operations in the decomposition tree; default: true.

◆ stopWhenIrregular

bool CMR_SEYMOUR_PARAMS::stopWhenIrregular

Whether to stop decomposing once irregularity is determined.

◆ stopWhenNeitherGraphicNorCoGraphic

bool CMR_SEYMOUR_PARAMS::stopWhenNeitherGraphicNorCoGraphic

Whether to stop decomposing once non-graphicness and non-cographicness (or not being network and not being conetwork) is determined.

◆ stopWhenNoncographic

bool CMR_SEYMOUR_PARAMS::stopWhenNoncographic

Whether to stop decomposing once non-cographicness (or being non-conetwork) is determined.

◆ stopWhenNongraphic

bool CMR_SEYMOUR_PARAMS::stopWhenNongraphic

Whether to stop decomposing once non-graphicness (or being non-network) is determined.

The documentation for this struct was generated from the following file:

/home/runner/work/cmr/cmr/include/cmr/seymour.h

Public Attributes