Regina Calculation Engine
Todo List
File matrixops.h
Feature (long-term): Add a routine to find the rank of an integer matrix; use this to show the rank of the matching equations.
Namespace regina

Bug: Derive from regina::boost::noncopyable where appropriate.

Feature (long-term): Enhance the test suite for the calculation engine.

Member regina::Dim2GluingPermSearcher::runSearch (long maxDepth=-1)
Feature: Allow cancellation of permutation set generation.
Member regina::formSigCensus (unsigned order, UseSignature use, void *useArgs=0)
Feature: Add support for symbols of differing case.
Class regina::NAbelianGroup
Optimise (long-term): Look at using sparse matrices for storage of SNF and the like.
Class regina::NBitmask
Optimise: Insist that sizeof(Piece) is a power of two, and replace expensive division/mod operations with cheap bit operations.
Class regina::NDiscSetTet
Bug (long-term): Have some error flag so we can barf politely if the number of normal discs of a given type does not fit into an unsigned long. See how this affects NDiscSetTetData also.
Member regina::NGenericFacetPairing< dim >::findAllPairings (unsigned nSimplices, NBoolSet boundary, int nBdryFacets, Use use, void *useArgs=0, bool newThread=false)

Optimise (long-term): When generating facet pairings, do some checking to eliminate cases in which simplex (k > 0) can be swapped with simplex 0 to produce a smaller representation of the same pairing.

Feature: Allow cancellation of facet pairing generation.

Member regina::NGenericTriangulation< dim >::isIsomorphicTo (const typename DimTraits< dim >::Triangulation &other) const
Optimise: Improve the complexity by choosing a simplex mapping from each component and following gluings to determine the others.
Member regina::NGluingPermSearcher::runSearch (long maxDepth=-1)
Feature: Allow cancellation of permutation set generation.
Class regina::NGraphLoop
Optimise: Speed up homology calculations involving orientable base spaces by adding rank afterwards, instead of adding generators for genus into the presentation matrix.
Class regina::NGraphPair
Optimise: Speed up homology calculations involving orientable base spaces by adding rank afterwards, instead of adding generators for genus into the presentation matrix.
Class regina::NGraphTriple
Optimise: Speed up homology calculations involving orientable base spaces by adding rank afterwards, instead of adding generators for genus into the presentation matrix.
Member regina::NGroupExpression::relabellingsThisToOther (const NGroupExpression &other, bool cyclic=false) const
Change this to use less heavyweight types and less deep copying.
Class regina::NGroupPresentation
Let's make intelligent simplify a tad more intelligent, and the GUI call a bit more safe. Perhaps parallelize the GUI call, and give users parameters to ensure it won't crash the computer. Also look at the FPGroup package. We should also have a simple way of creating NGroupPresentation objects directly from text strings. We would like to have something like NGroupPresentation( numGens, "abAAB", "bccd" ) etc., with arbitrary numbers of relators. Maybe std::tuple. Or "variadic templates"?
Member regina::NGroupPresentation::prettyRewritingDetail ()
As a final step, make elementary simplifications to aid in seeing standard relators like commutators.
Member regina::NGroupPresentation::recogniseGroup () const
Feature (long-term): Make this recognition more effective.
Member regina::NGroupPresentation::smallCancellationDetail ()
Optimise (long-term): This routine could use some small tweaks - recognition of utility of some score==0 moves, such as commutators, for example.
Class regina::NHomGroupPresentation
Add a routine to attempt to verify validity of homomorphism.
Class regina::NHomMarkedAbelianGroup

Optimise (long-term): preImageOf in CC and SNF coordinates. This routine would return a generating list of elements in the preimage, thought of as an affine subspace. Or maybe just one element together with the kernel inclusion. IMO smarter to be a list because that way there's a more pleasant way to make it empty. Or we could have a variety of routines among these themes. Store some minimal data for efficient computations of preImage, eventually replacing the internals of inverseHom() with a more flexible set of tools. Also add an isInImage() in various coordinates.

Optimise (long-term): writeTextShort() have completely different set of descriptors if an endomorphism domain = range (not so important at the moment though). New descriptors would include things like automorphism, projection, differential, finite order, etc.

Optimise (long-term): Add map factorization, so that every homomorphism can be split as a composite of a projection followed by an inclusion. Add kernelInclusion(), coKerMap(), etc. Add a liftMap() call, i.e., a procedure to find a lift of a map if one exists.

Class regina::NIsomorphism
Feature: Composition of isomorphisms.
Class regina::NMarkedAbelianGroup

Optimise (long-term): Look at using sparse matrices for storage of SNF and the like.

Testsuite additions: isBoundary(), boundaryMap(), writeAsBdry(), cycleGen().

Class regina::NNormalSurface

Feature: Calculation of Euler characteristic and orientability for non-compact surfaces.

Feature (long-term): Determine which faces in the solution space a normal surface belongs to.

Member regina::NNormalSurface::isCentral () const
Optimise: Cache results.
Member regina::NNormalSurface::isCompressingDisc (bool knownConnected=false) const

Optimise: Reimplement this to avoid cutting along surfaces.

Bug: Check for absurdly large numbers of discs and bail accordingly.

Member regina::NNormalSurface::isSplitting () const
Optimise: Cache results.
Member regina::NNormalSurface::isThinEdgeLink () const
Optimise: Cache results.
Member regina::NNormalSurface::isVertexLink () const
Optimise: Cache results.
Member regina::NNormalSurface::isVertexLinking () const
Optimise: Cache results.
Class regina::NNormalSurfaceList

Feature: Allow custom matching equations.

Feature: Allow enumeration with some coordinates explicitly set to zero.

Feature: Allow generating only closed surfaces.

Feature: Generate facets of the solution space representing embedded surfaces.

Member regina::NNormalSurfaceList::filterForDisjointPairs () const
Deal properly with surfaces that are too large to handle.
Member regina::NNormalSurfaceList::filterForPotentiallyIncompressible () const
Add progress tracking.
Class regina::NNormalSurfaceVector
Optimise (long-term): Investigate using sparse vectors for storage.
Class regina::NNormalSurfaceVectorMirrored
Bug: Allow modification of the vector by overwriting setValue(); this will require documentation changes in both this class and in NNormalSurfaceVector.
Class regina::NPacket
Feature: Provide automatic name selection/specification upon child packet insertion.
Member regina::NPrimes::primeDecomp (const NLargeInteger &n)
Optimise: Add a version that does not return the factors by value.
Member regina::NPrimes::primePowerDecomp (const NLargeInteger &n)

Optimise: Implement this routine natively to avoid the overhead of the temporary primeDecomp() vector.

Optimise: Add a version that does not return the factors by value.

Class regina::NSatRegion
Feature: Have this class track the boundary components properly, with annuli grouped and oriented according to the region boundaries (as opposed to individual block boundaries).
Class regina::NSFSpace

Feature (long-term): Implement recognition of more common names.

Feature (long-term): Implement triangulation construction and homology calculation for more Seifert fibred spaces.

Class regina::NSurfaceFilter
Feature: Implement property lastAppliedTo.
Class regina::NTorusBundle
Feature: Implement the == operator for finding conjugate and inverse matrices.
Class regina::NTriangulation

Feature: Is the boundary incompressible?

Feature (long-term): Am I obviously a handlebody? (Simplify and see if there is nothing left). Am I obviously not a handlebody? (Compare homology with boundary homology).

Feature (long-term): Is the triangulation Haken?

Feature (long-term): What is the Heegaard genus?

Feature (long-term): Have a subcomplex as a child packet of a triangulation. Include routines to crush a subcomplex or to expand a subcomplex to a normal surface.

Feature (long-term): Implement writeTextLong() for skeletal objects.

Member regina::NTriangulation::idealToFinite (bool forceDivision=false)
Optimise (long-term): Have this routine only use as many tetrahedra as are necessary, leaving finite vertices alone.
Member regina::NTriangulation::intelligentSimplify ()
Optimise: Include random 2-3 moves to get out of wells.

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 (