Regina Calculation Engine
Public Types | Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
regina::NGenericGluingPerms< dim > Class Template Reference

A dimension-agnostic base class that represents a specific set of gluing permutations to complement a particular pairwise matching of simplex facets. More...

#include <census/ngenericgluingperms.h>

Public Types

typedef DimTraits< dim >
::FacetPairing 
FacetPairing
 
typedef DimTraits< dim >::Perm Perm
 
typedef DimTraits< dim >::Simplex Simplex
 
typedef DimTraits< dim >
::Triangulation 
Triangulation
 

Public Member Functions

 NGenericGluingPerms (const NGenericGluingPerms< dim > &cloneMe)
 Creates a new set of gluing permutations that is a clone of the given permutation set. More...
 
 NGenericGluingPerms (std::istream &in)
 Reads a new set of gluing permutations from the given input stream. More...
 
virtual ~NGenericGluingPerms ()
 Deallocates any memory used by this structure. More...
 
bool inputError () const
 Was an error found during construction from an input stream? More...
 
unsigned size () const
 Returns the total number of simplices under consideration. More...
 
const FacetPairing * getFacetPairing () const
 Returns the specific pairing of simplex facets that this set of gluing permutations complements. More...
 
Perm gluingPerm (const NFacetSpec< dim > &source) const
 Returns the gluing permutation associated with the given simplex facet. More...
 
Perm gluingPerm (unsigned simp, unsigned facet) const
 Returns the gluing permutation associated with the given simplex facet. More...
 
Triangulation * triangulate () const
 Returns a newly created triangulation as modelled by this set of gluing permutations and the associated simplex facet pairing. More...
 
virtual void dumpData (std::ostream &out) const
 Dumps all internal data in a plain text format to the given output stream. More...
 

Protected Member Functions

 NGenericGluingPerms (const FacetPairing *pairing)
 Creates a new permutation set. More...
 
int & permIndex (const NFacetSpec< dim > &source)
 Returns the index into array Perm::Sn_1 describing how the the given facet is joined to its partner. More...
 
int & permIndex (unsigned simp, unsigned facet)
 Returns the index into array Perm::Sn_1 describing how the the given facet is joined to its partner. More...
 
const int & permIndex (const NFacetSpec< dim > &source) const
 Returns the index into array Perm::Sn_1 describing how the the given facet is joined to its partner. More...
 
const int & permIndex (unsigned simp, unsigned facet) const
 Returns the index into array Perm::Sn_1 describing how the the given facet is joined to its partner. More...
 
int gluingToIndex (const NFacetSpec< dim > &source, const Perm &gluing) const
 Returns the index into array Perm::Sn_1 corresponding to the given gluing permutation from the given facet to its partner. More...
 
int gluingToIndex (unsigned simp, unsigned facet, const Perm &gluing) const
 Returns the index into array Perm::Sn_1 corresponding to the given gluing permutation from the given facet to its partner. More...
 
Perm indexToGluing (const NFacetSpec< dim > &source, int index) const
 Returns the gluing permutation from the given facet to its partner that corresponds to the given index into array Perm::Sn_1. More...
 
Perm indexToGluing (unsigned simp, unsigned facet, int index) const
 Returns the gluing permutation from the given facet to its partner that corresponds to the given index into array Perm::Sn_1. More...
 

Protected Attributes

const FacetPairing * pairing_
 The facet pairing that this permutation set complements. More...
 
int * permIndices_
 The index into array Perm::Sn_1 describing how each simplex facet is glued to its partner. More...
 
bool inputError_
 Has an error occurred during construction from an input stream? More...
 

Detailed Description

template<int dim>
class regina::NGenericGluingPerms< dim >

A dimension-agnostic base class that represents a specific set of gluing permutations to complement a particular pairwise matching of simplex facets.

Each dimension that Regina works with (2, 3 and 4) offers its own subclass, in some cases with richer functionality. Users should not need to work with this template base class directly.

Given a pairwise matching of facets (as described by class NGenericFacetPairing<dim>), each facet that is matched with some other facet will have an associated permutation of (dim + 1) elements.

If a facet is matched with some other facet, the two associated permutations in this set will be inverses. If a facet is left deliberately unmatched, it will have no associated permutation in this set.

Such a set of permutations models part of the structure of a triangulation, in which each simplex facet that is glued to another facet has a corresponding gluing permutation (and the matched facet has the inverse gluing permutation).

Precondition
The dimension argument dim is either 2, 3 or 4.
Python:
Not present.

Constructor & Destructor Documentation

template<int dim>
regina::NGenericGluingPerms< dim >::NGenericGluingPerms ( const NGenericGluingPerms< dim > &  cloneMe)

Creates a new set of gluing permutations that is a clone of the given permutation set.

Parameters
cloneMethe gluing permutations to clone.
template<int dim>
regina::NGenericGluingPerms< dim >::NGenericGluingPerms ( std::istream &  in)

Reads a new set of gluing permutations from the given input stream.

This routine reads data in the format written by dumpData().

If the data found in the input stream is invalid or incorrectly formatted, the routine inputError() will return true but the contents of this object will be otherwise undefined.

Warning
The data format is liable to change between Regina releases. Data in this format should be used on a short-term temporary basis only.
Parameters
inthe input stream from which to read.
template<int dim>
regina::NGenericGluingPerms< dim >::~NGenericGluingPerms ( )
inlinevirtual

Deallocates any memory used by this structure.

template<int dim>
regina::NGenericGluingPerms< dim >::NGenericGluingPerms ( const FacetPairing *  pairing)
inlineprotected

Creates a new permutation set.

All internal arrays will be allocated but not initialised.

Precondition
The given facet pairing is connected, i.e., it is possible to reach any simplex from any other simplex via a series of matched facet pairs.
The given facet pairing is in canonical form as described by NGenericFacetPairing::isCanonical(). Note that all facet pairings constructed by NGenericFacetPairing::findAllPairings() are of this form.
Parameters
pairingthe specific pairing of simplex facets that this permutation set will complement.

Member Function Documentation

template<int dim>
virtual void regina::NGenericGluingPerms< dim >::dumpData ( std::ostream &  out) const
virtual

Dumps all internal data in a plain text format to the given output stream.

This object can be recreated from this text data by calling the input stream constructor for this class.

This routine may be useful for transferring objects from one processor to another.

Note that subclass data is written after superclass data, so it is safe to dump data from a subclass and then recreate a new superclass object from that data (though subclass-specific information will of course be lost).

Warning
The data format is liable to change between Regina releases. Data in this format should be used on a short-term temporary basis only.
Parameters
outthe output stream to which the data should be written.

Reimplemented in regina::NHyperbolicMinSearcher, regina::NClosedPrimeMinSearcher, regina::NCompactSearcher, regina::NEulerSearcher, regina::NGluingPermSearcher, and regina::Dim2GluingPermSearcher.

template<int dim>
const NGenericGluingPerms< dim >::FacetPairing * regina::NGenericGluingPerms< dim >::getFacetPairing ( ) const
inline

Returns the specific pairing of simplex facets that this set of gluing permutations complements.

Returns
the corresponding simplex facet pairing.
template<int dim>
NGenericGluingPerms< dim >::Perm regina::NGenericGluingPerms< dim >::gluingPerm ( const NFacetSpec< dim > &  source) const
inline

Returns the gluing permutation associated with the given simplex facet.

Precondition
The given facet is actually paired with some other facet in the underlying pairwise matching (see routine getFacetPairing()).
The given facet is a real simplex facet (not boundary, before-the-start or past-the-end).
Parameters
sourcethe simplex facet under investigation.
Returns
the associated gluing permutation.
template<int dim>
NGenericGluingPerms< dim >::Perm regina::NGenericGluingPerms< dim >::gluingPerm ( unsigned  simp,
unsigned  facet 
) const
inline

Returns the gluing permutation associated with the given simplex facet.

Precondition
The given facet is actually paired with some other facet in the underlying pairwise matching (see routine getFacetPairing()).
Parameters
simpthe simplex under investigation (this must be strictly less than the total number of simplices under consideration).
facetthe facet of the given simplex under investigation (between 0 and dim inclusive).
Returns
the associated gluing permutation.
template<int dim>
int regina::NGenericGluingPerms< dim >::gluingToIndex ( const NFacetSpec< dim > &  source,
const Perm &  gluing 
) const
protected

Returns the index into array Perm::Sn_1 corresponding to the given gluing permutation from the given facet to its partner.

This need not be the index into Perm::Sn_1 that is currently stored for the given facet.

Indices into array Perm::Sn_1 are stored internally in the array permIndices_. Full gluing permutations on the other hand are used in constructing triangulations.

Precondition
The given simplex facet has a partner according to the underlying facet pairing, i.e., is not a boundary facet.
If the given simplex facet and its partner are facets x and y of their respective simplices, then the given gluing permutation maps x to y.
Parameters
sourcethe simplex facet under investigation.
gluinga possible gluing permutation from the given simplex facet to its partner according to the underlying facet pairing.
Returns
the index into Perm::Sn_1 corresponding to the given gluing permutation; this will be between 0 and dim!-1 inclusive.
template<int dim>
int regina::NGenericGluingPerms< dim >::gluingToIndex ( unsigned  simp,
unsigned  facet,
const Perm &  gluing 
) const
protected

Returns the index into array Perm::Sn_1 corresponding to the given gluing permutation from the given facet to its partner.

This need not be the index into Perm::Sn_1 that is currently stored for the given facet.

Indices into array Perm::Sn_1 are stored internally in the array permIndices_. Full gluing permutations on the other hand are used in constructing triangulations.

Precondition
The given simplex facet has a partner according to the underlying facet pairing, i.e., is not a boundary facet.
If the given simplex facet and its partner are facets x and y of their respective simplices, then the given gluing permutation maps x to y.
Parameters
simpthe simplex under investigation; this must be strictly less than the total number of simplices under consideration.
facetthe facet of the given simplex under investigation; this must be between 0 and dim inclusive.
gluinga possible gluing permutation from the given simplex facet to its partner according to the underlying facet pairing.
Returns
the index into Perm::Sn_1 corresponding to the given gluing permutation; this will be between 0 and dim!-1 inclusive.
template<int dim>
NGenericGluingPerms< dim >::Perm regina::NGenericGluingPerms< dim >::indexToGluing ( const NFacetSpec< dim > &  source,
int  index 
) const
inlineprotected

Returns the gluing permutation from the given facet to its partner that corresponds to the given index into array Perm::Sn_1.

This index into Perm::Sn_1 need not be the index that is currently stored for the given facet.

Indices into array Perm::Sn_1 are stored internally in the array permIndices_. Full gluing permutations on the other hand are used in constructing triangulations.

If the given simplex facet and its partner according to the underlying facet pairing are facets x and y of their respective simplices, then the resulting gluing permutation will map x to y.

Precondition
The given simplex facet has a partner according to the underlying facet pairing, i.e., is not a boundary facet.
Parameters
sourcethe simplex facet under investigation.
indexan index into Perm::Sn_1; this must be between 0 and dim!-1 inclusive.
Returns
the gluing permutation corresponding to the given index into Perm::Sn_1.
template<int dim>
NGenericGluingPerms< dim >::Perm regina::NGenericGluingPerms< dim >::indexToGluing ( unsigned  simp,
unsigned  facet,
int  index 
) const
inlineprotected

Returns the gluing permutation from the given facet to its partner that corresponds to the given index into array Perm::Sn_1.

This index into Perm::Sn_1 need not be the index that is currently stored for the given facet.

Indices into array Perm::Sn_1 are stored internally in the array permIndices_. Full gluing permutations on the other hand are used in constructing triangulations.

If the given simplex facet and its partner according to the underlying facet pairing are facets x and y of their respective simplices, then the resulting gluing permutation will map x to y.

Precondition
The given simplex facet has a partner according to the underlying facet pairing, i.e., is not a boundary facet.
Parameters
simpthe simplex under investigation; this must be strictly less than the total number of simplices under consideration.
facetthe facet of the given simplex under investigation; this must be between 0 and dim inclusive.
indexan index into Perm::Sn_1; this must be between 0 and dim!-1 inclusive.
Returns
the gluing permutation corresponding to the given index into Perm::Sn_1.
template<int dim>
bool regina::NGenericGluingPerms< dim >::inputError ( ) const
inline

Was an error found during construction from an input stream?

This routine returns true if an input stream constructor was used to create this object but the data in the input stream was invalid or incorrectly formatted.

If a different constructor was called (i.e., no input stream was used), then this routine will always return false.

Returns
true if an error occurred during construction from an input stream, or false otherwise.
template<int dim>
int & regina::NGenericGluingPerms< dim >::permIndex ( const NFacetSpec< dim > &  source)
inlineprotected

Returns the index into array Perm::Sn_1 describing how the the given facet is joined to its partner.

Note that this permutation is not a gluing permutation as such, but rather a permutation of 0,...,dim-1 only. For a real facet gluing permutation, see routine gluingPerm().

Precondition
The given facet is a real simplex facet (not boundary, before-the-start or past-the-end).
Parameters
sourcethe simplex facet under investigation.
Returns
a reference to the corresponding array index.
template<int dim>
int & regina::NGenericGluingPerms< dim >::permIndex ( unsigned  simp,
unsigned  facet 
)
inlineprotected

Returns the index into array Perm::Sn_1 describing how the the given facet is joined to its partner.

Note that this permutation is not a gluing permutation as such, but rather a permutation of 0,...,dim-1 only. For a real facet gluing permutation, see routine gluingPerm().

Parameters
simpthe simplex under investigation (this must be strictly less than the total number of simplices under consideration).
facetthe facet of the given simplex under investigation (between 0 and dim inclusive).
Returns
a reference to the corresponding array index.
template<int dim>
const int & regina::NGenericGluingPerms< dim >::permIndex ( const NFacetSpec< dim > &  source) const
inlineprotected

Returns the index into array Perm::Sn_1 describing how the the given facet is joined to its partner.

Note that this permutation is not a gluing permutation as such, but rather a permutation of 0,...,dim-1 only. For a real facet gluing permutation, see routine gluingPerm().

Precondition
The given facet is a real simplex facet (not boundary, before-the-start or past-the-end).
Parameters
sourcethe simplex facet under investigation.
Returns
a reference to the corresponding array index.
template<int dim>
const int & regina::NGenericGluingPerms< dim >::permIndex ( unsigned  simp,
unsigned  facet 
) const
inlineprotected

Returns the index into array Perm::Sn_1 describing how the the given facet is joined to its partner.

Note that this permutation is not a gluing permutation as such, but rather a permutation of 0,...,dim-1 only. For a real facet gluing permutation, see routine gluingPerm().

Parameters
simpthe simplex under investigation (this must be strictly less than the total number of simplices under consideration).
facetthe facet of the given simplex under investigation (between 0 and dim inclusive).
Returns
a reference to the corresponding array index.
template<int dim>
unsigned regina::NGenericGluingPerms< dim >::size ( ) const
inline

Returns the total number of simplices under consideration.

Returns
the number of simplices under consideration.
template<int dim>
Triangulation* regina::NGenericGluingPerms< dim >::triangulate ( ) const

Returns a newly created triangulation as modelled by this set of gluing permutations and the associated simplex facet pairing.

Each matched pair of facets and their associated permutations will be realised as two simplex facets in the triangulation glued together with the corresponding gluing permutation. Each unmatched facet will be realised as a boundary facet in the triangulation.

It is the responsibility of the caller of this routine to delete this triangulation once it is no longer required.

Returns
a newly created triangulation modelled by this structure.

Member Data Documentation

template<int dim>
bool regina::NGenericGluingPerms< dim >::inputError_
protected

Has an error occurred during construction from an input stream?

template<int dim>
const FacetPairing* regina::NGenericGluingPerms< dim >::pairing_
protected

The facet pairing that this permutation set complements.

This is guaranteed to be the minimal representative of its facet pairing isomorphism class.

template<int dim>
int* regina::NGenericGluingPerms< dim >::permIndices_
protected

The index into array Perm::Sn_1 describing how each simplex facet is glued to its partner.

Note that this is not a gluing permutation as such but rather a permutation of 0,...,dim-1 only (see the routines gluingToIndex() and indexToGluing() for conversions). If a permutation has not yet been selected (e.g., if this permutation set is still under construction) then this index is -1.


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).