In this file we record the changes since the first GAP 4 release of the GUAVA package. Version 2.7: (5-2005) o Cen Tjhai ("cjt") added as author. o cjt: Complete rewrite of the files in the tbl subdirectory. There are (as of May 11, 2006) as updated as Brouwer's online tables (www.win.tue.nl/~aeb/voorlincod.html). o cjt: Created two functions in codeman.g*, SubCode and ConstructionB2Code. The ConstructionB2Code function is empty and to be implemented in a future version. o wdj: GUAVA Manual changes. Version 2.6: Forked off a branch of GUAVA whihc is entirely GPL'd code. (None of Leon's code is included.) Otherwise, same as 2.5. This branch is used in SAGE (sage.scipy.org). Version 2.5: (1-2006) o Fixed undesired feature in Decodeword (spotten by Cayanne McFarlane). o Added MinimumWeightWords to manual; modified GAP code for MinimumWeightWords to speed it up. o Modified CheckMatCode to "Set" *mutable* generator and check matrices. o Added BitFlipDecoder, a fast decoder for LDPC codes (written with Gordon McDonald). o Added GuavaVersion and guava_version o Added FerrorDesignCode, written with Peter Mayr at Linz (one of the SONATA authors). This requires SONATA be loaded. o Added QQRCodeNC (written with Greg Coy). o Miscellaneous additions to the GUAVA manual. Version 2.4: (6-2005) Minor bug fix - o In MatrixRepresentationOnRiemannRochSpaceP1, cleaned up code and fixed a bug (GAP does not process 1 the same as x^0 in some cases). o Fixed spelling error in guava.tst file. Version 2.3: (5-2005) o added PermutationDecoderNC, CyclicDecoder o change PermutationGroup in PermutationDecoder to PermutationAutomorphismGroup o in codegen.gi, line 2066, replace C.GeneratorMat by C.EvaluationMat, and then add the existence of this extra record component to the documentation o classical Goppa = AG codes over P^1 o curve record data structure for plane curves and some associated functions o divisor record data structure for curves (only used for P^1) and some associated functions o automorphism group of a divisor on P^1 (very slow) o function computing matrix representation of group action on Riemann-Roch space (in P^1 case only, also very slow) o one point AG codes o nicer evaluation codes in 2-d o miscellaneous functions for multivariate polynomials o new section on algebraic geometric codes in manual Version 2.0002 (5-2005) o A renaming of GUAVA 2.0, for the GAP 4.4.5 release. Version 2.0001: (12-2004) o Merely aded PolynomialByExtRepNC to GUAVA. (A *temporary* addition to last until GAP 4.4.5 was released.) Version 2.0: (12-2004) o Changed `ViewObj` method for random linear codes, speeding up the implementation of the RandomLinearCode command. o Modified BCHCode and RootsCode implementation. o Corrected bug in UpperBoundElias. o Rewrote GUAVA documentation into GAPDoc, with many revisions. o Added EvaluationCode and related codes (GeneralizedReedMullerCode, GeneralizedReedSolomonCode, OnePointAGCode, joint with Jason McGowan) o Added interpolation decoding method for GeneralizedReedSolomonCode (joint with Jason McGowan), GeneralizedReedSolomonDecoder. o Added S. Gao decoding method for GeneralizedReedSolomonCode, GeneralizedReedSolomonDecoderGao. o Fixed bug in MinimumDistance (wrong result if G=(I|A) and A had a row of 0s) o MinimumDistanceRandom algorithm implemented in non-binary case (joint with Wayne Irons). o Added list-decoding algorithm GeneralizedReedSolomonListDecoder (joint with Clifton Lennon) and related commands (some undocumented). o Bug fix for SortedGaloisFieldElements (used to construct Gabidulin codes). o CalculateLinearCodeCoveringRadius changed to a slightly faster algorithm. o minor bug fix for ExhaustiveSearchCoveringRadius o minor bug fix for IncreaseCoveringRadiusLowerBound o Changed ConstantWeightSubcode so it does not call Leon's program if wtdist is not installed. Moreover, the procedure interfacing with the binary had a bug, which was fixed. o Added check in AutomorphismGroup: if Leon's desauto is not compiled (e.g., on a windows machine) then it calls PermutationGroup command instead. o Added Decodeword (which also works for non-linear codes) o Added NearestNeighborDecodewords (for linear codes) o Added NearestNeighborGRSDecodewords (for GRS codes) o Added PermutationAutomorphismGroup (which will replace the poorly named PermutationGroup command added in version 1.9) o Moved several decoding commands from codeops.gi to decoders.gi (with no change in functionality). o Added LowerBoundGilbertVarshamov and LowerBoundSpherePacking. o Added DivisorsMultivariatePolynomial and related commands (some undocumented). o Released under the GNU GPL. Version 1.9: (3-2004) o Faster MinimumDistance algorithm (joint with Aron Foster, a student). o MinimumDistanceLeon algorithm (joint with Aron Foster) in binary case. o Faster PutStandard form algorithm (with Frank Luebeck). o New PermutationGroup command (for possibly non-binary codes). o New PermutationDecode command. Version 1.82: (7-2003) o Slight changes to prepare for the different loading mechanism for GAP packages used in the upcoming GAP 4.4. Version 1.8: o New commands for toric codes. Version 1.7: (2-2003) o Various typos in manual fixed. o lib/codecstr.g[di]: `AmalgamatedDirectSumCode' previously misspelt as `AmalgatedDirectSumCode' corrected. o Version Id headers in doc/* and lib/* files added. o README: updated. o init.g: now checks the C code has been compiled and warns of missing functionality if not compiled. o banner.g, lib/setup.g: banner split off as a separate file. o PkgInfo.g, CHANGES (this file): added. Version 1.6: (9-2001) New maintainer: David Joyner. o Bugs in `IsAffineCode' and `MinimumDistance' (reported by Akihiro Munemasa, who also supplied a fix for the `IsAffineCode' bug) fixed. o Manual thoroughly reworked. HTML manual made available. Version 1.5: GAP 4.2 version. Not compatible with GAP 4.1. Version 1.4: First GAP4 version by Lea Ruscio. Created for GAP 4.1. Incompatible with GAP 4.2. Version 1.3: Last GAP3 version. - David Joyner -- January 4, 2006