Regina Calculation Engine
Protected Member Functions | Static Protected Member Functions | Protected Attributes | List of all members
regina::BanConstraintBase Class Reference

A base class for additional banning and marking constraints that we can place on tree traversal algorithms. More...

#include <enumerate/ntreeconstraint.h>

Inheritance diagram for regina::BanConstraintBase:
regina::BanBoundary regina::BanNone regina::BanTorusBoundary

Protected Member Functions

 BanConstraintBase (const NTriangulation *tri, int coords)
 Constructs and initialises the banned_ and marked_ arrays to be entirely false. More...
 
 ~BanConstraintBase ()
 Destroys this object and all associated data. More...
 
template<class LPConstraint , typename Integer >
void enforceBans (LPData< LPConstraint, Integer > &lp) const
 Enforces all bans described by this class in the given tableaux. More...
 
void init (const int *columnPerm)
 Identifies which coordinates to ban and mark, and records the corresponding tableaux columns in the banned_ and marked_ arrays respectively. More...
 

Static Protected Member Functions

static bool supported (NormalCoords coords)
 Indicates whether the given coordinate system is supported by this constraint class. More...
 

Protected Attributes

const NTriangulationtri_
 The triangulation with which we are working. More...
 
int coords_
 The normal or almost normal coordinate system in which we are working. More...
 
bool * banned_
 Indicates which columns of a tableaux correspond to banned coordinates (e.g., banned normal disc types). More...
 
bool * marked_
 Indicates which columns of a tableaux correspond to marked coordinates (e.g., marked normal disc types). More...
 

Detailed Description

A base class for additional banning and marking constraints that we can place on tree traversal algorithms.

This is used with NTreeEnumeration, NTreeSingleSoln and related algorithms for enumerating and locating normal surfaces and angle structures in a 3-manifold triangulation.

This class adds constraints of two types:

All of these constraints operate only on normal or angle structure coordinates in the underlying tableaux (and in particular not the additional variables introduced by additional linear constraints, as described by LPConstraintBase and its subclasses).

Currently marking is used in the following ways:

At present, marking is not used at all for quadrilateral coordinates or angle structures. However, marking is a very new feature, and this concept may be expanded in future versions of Regina.

This class does not record disc types in the order of their normal or angle structure coordinates; instead it records them in the order of their columns in a tableaux for linear programming (as used in LPInitialTableaux). This means that there is a little more work required in setting up the initial lists of banned and marked columns, but then these lists are easy to use on the fly during tree traversal algorithms.

This base class provides limited functionality (as documented below). Subclasses must implement a constructor (which, like this base class, takes a triangulation and a coordinate system), must implement init() which determines which coordinates are banned and/or marked, and must implement supported(), which indicates which normal or angle structure coordinate system this constraint class can work with.

Warning
The API for this class has not yet been finalised. This means that the class interface may change in new versions of Regina, without maintaining backward compatibility. If you use this class directly in your own code, please watch the detailed changelogs upon new releases to see if you need to make changes to your code.
Python:
Not present.

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

Copyright © 1999-2014, The Regina development team
This software is released under the GNU General Public License, with some additional permissions; see the source code for details.
For further information, or to submit a bug or other problem, please contact Ben Burton (bab@debian.org).