GAP

### Main Branches

 This is a page on GAP 3, which is still available, but no longer supported. The present version is GAP 4  (See  Status of GAP 3).

## GAP 3 Release 4.4 Bug Fixes

The precompiled DOS binaries provided before May 2nd 1997 contained bugs. You should get them anew. (This has been fixed in the distribution files.)

There is a bug in the isomorphism test of the Sisyphos share package. A fixed and updated version is here

An and updated version (2.4) of the Specht share package has been released. Specht 2.4

The share package Monoid has been added anew in version 2.2. Monoid 2.2

The following files fix serious bugs in the library and the share packages. Get all and unpack them in the home directory of your GAP 3 distribution (the directory containing the 'lib' and 'etc' directories) using 'unzoo -x fixy.zoo' to get everything fixed. You can remove the files 'description*' afterwards.

fix1.zoo
This bugfix fixes minor bugs with the usage of reflection subgroups in conjunction with braids or hecke elements. It also fixes serious problems with the computation of Kazhdan-Lusztig polynomials which in the distributed version fails for reflection subgroups and Kazhdan-Lusztig bases which in the distributed version fail when a mu coefficient is not equal to 1.
by Jean Michel, 26-May-97
fix2.zoo
This fix corrects:
1) A potential 'division by zero' error in the polynomial factorization routine over Z when trying to reduce coefficients.
2) A wrong result of 'IsSubset' for FpGroups if the FpGroup already contains elements.
3) A missing record component, leading to a syntax error, in the element conjugacy test for matrix groups.
Errors 1 and 3 will yield GAP 3 to enter the 'brk' loop, error 2 may yield wrong results!
by Alexander Hulpke, 10-Jun-97
fix3.zoo
This fix corrects an error in the function 'IsFiniteDeterministic' of the 'GRIM' share package.
by Robert Beals, 23-Jun-97
fix4.zoo
This fix corrects:
1) An error in the Tietze transformation routines when handling presentations including a redundant generator g and a relator of form g^2 or g^-2.
2) An error in 'RewriteSubgroupRelators' when encountering the empty word as group relator.
by Volkmar Felsch, 25-Jun-97
fix5.zoo
This fix corrects:
1) An error in the homomorphism test for mappings from finitely presented groups.
2) An error in the homomorphism test for mappings to finitely presented groups (it is not possible to simply evaluate relators).
3) An error in 'PermChars'.
by Götz Pfeiffer, Cosimo Fornano and Alexander Hulpke, 1-Jul-97
fix6.zoo
This fix adds documentation for the small groups library.
by Bettina Eick, 3-Jul-97
fix7.zoo
This fix corrects:
1) An error in the 'PreImagesRepresentative' code for homomorphisms between AgGroups.
2) An error in the 'Centralizer' code for AgGroups that may introduce duplicate parent groups.
3) An error in 'RealClassesCharTable'.
4) A compiler problem in the DOS version. (With level 2 optimization the Kernel function TreeEntry does not work.)
5) Potentially stray pointers in kernel routines for finitely presented groups if a garbage collection is issued in between.
6) Adaption of the XGAP share package to changes in the Tietze transformation routines in GAP 3.4.4.
7) Upgrade of the MeatAxe share package to the C-Meataxe 2.2.3 (to avoid problems under Linux).
As this fix changes the source you will have to recompile. We have precomplied binaries (archived) for DOS, and Macintoshes.
If you use the MeatAxe share package you will also have to recompile the MeatAxe binaries.
by Thomas Breuer, Frank Celler, Volkmar Felsch, Alexander Hulpke, and Werner Nickel, 12-Sep-97
fix8.zoo
This fix provides:
1) A workaround for a kernel problem in auxiliary routines for the function 'AbelianInvariantsSubgroupFpGroupMtc'.
2) Corrections in the sun-...-cc target in the Makefile.
3) A new target for Linux Power-Pc Machines in the Makefile.
4) Correction for the creation of the path name of share packages if the operating system does not use '/' as directory separator.
5) Correction for an error in the comparison routine for vector spaces.
by Thomas Breuer, Volkmar Felsch, Alexander Hulpke, and Werner Nickel, 15-Oct-97
fix9.zoo
This fix corrects:
1) A problem with NaturalHomomorphism' for subgroups of a solvable permutation group, obtained via a composition series.
2) Random' for the trivial subgroup of an AgGroup.
3) The \in test for elements in automorphism groups.
by Alexander Hulpke, 13-Nov-97
fix10.zoo
This fix corrects:
1) A problem in DeterminantChar',
2) Two problems in CyclotomicField',
3) A problem in the calculation of character tables for permutation groups.
4) An error in the meataxe' share package.
5) An error in the Intersection' Routine for residue classes.
6) A corresponding manual error.
7) An error in Units' for GaussianIntegers'.
by Thomas Breuer and Alexander Hulpke, 27-Feb-98
fix11.zoo
This fix corrects:
1) A problem with CharacterDegrees' not finishing for some groups,
2) An error in Resultant' when applied to multivariate polynomials,
3) An error when computing the automorphism group of small cyclic groups,
4) An error when intersecting groups with cosets,
5) An error when sorting conjugacy classes during the calculation of character tables.
6) It also provides a workaround for a problem in OneCocycles'.
by Marina Avitabile and Alexander Hulpke, 10-Apr-98
fix12.zoo
This fix corrects:
1) a problem with the arithmetic for finite fields,
2) a problem with the functions Coefficients' and in' for elements of row spaces.
See the included file description12' for more details. (25-Nov-1999.)
fix13.zoo
This fix corrects:
1) A bug in the function PresentationViaCosetTable'.
2) A bug in the functions ImfInvariants' and DisplayImfInvariants'.
See the included file description13' for more details. (18-May-2000.)