Update Info:
*Base Release*

Available in Package Hub : 15

Available in Package Hub : 15

AArch64 | |

ppc64le | |

s390x | |

x86-64 |

gap-rcwa

- Update to new upstream release 4.6.1 * No user-visible changes (only pkg metadata)

- Update to new upstream release 4.6.0 * Determining transitivity and computing transitivity certificates has been made more efficient in some cases, and an operation `SimplifiedCertificate' has been added. * An operation `EpimorphismsUpToAutomorphisms' has been added, together with a method which computes all epimorphisms from a given finitely presented group to a given finite group up to automorphisms of the latter. * Lists 'redundant_generator', 'spheresizebound_4', 'spheresizebound_6', 'spheresizebound_12' and 'spheresizebound_24' have been added to the database of groups generated by 3 class transpositions. * Single-argument methods for `TransitionMatrix' and `TransitionGraph' have been added.

- Update to new upstream release 4.5.1 * RCWA now prints a warning if GAP is run in legacy 32-bit mode due to the size of integers in ranges in 32-bit GAP which may make some computations fail and trigger error messages. * A further method for `EpimorphismFromFpGroup' has been added. This method allows to limit the search space to elements with not more than a given number of affine parts. * Attributes `DecompositionIntoPermutationalAndOrderPreservingElement' and `SignInOddCTPZ' have been added. * The following components have been added to the database of groups generated by 3 class transpositions: 'minwordlengthnonbalanced', 'minwordlengthcoprimemultdiv', 'epifromfpgrouptocollatzgroup_c' and 'epifromfpgrouptocollatzgroup_t'. * The method for `RestrictedBall' for computing restricted balls in rcwa monoids does now interpret options "boundaffineparts" and "boundnonidentityaffineparts". If set, the specified bound is on the number of affine parts, respectively, on the number of affine parts distinct from the identity, rather than on the modulus of the mapping. * An operation `HashValueOfRcwaMapping' has been added. The purpose of the hash values is to allow faster searching of rcwa mappings by algorithms. * Now the operations `Support', `IncreasingOn', `DecreasingOn', `ShiftsUpOn', `ShiftsDownOn', `LargestSourcesOfAffineMappings' and `Multpk' return their result in sparse representation if the argument is in sparse representation. * An operation `RefinementSequence' has been added.

- Update to new upstream release 4.4.1 * A `Random` method for finitely generated rcwa groups and given word length has been added. * Many newly found subgroup relations have been added to the database of groups generated by 3 class transpositions which interchange residue classes with moduli <= 6. * A new method for computing the order of an element of CT(Z) has been added. Its use can be triggered by setting the option "new_order" when calling the operation `Order`. This method is sometimes faster and sometimes slower than the default method. * The function `PrimeSwitch' has been turned into an operation, and new methods PrimeSwitch(p,r,m) and PrimeSwitch(p,cl) to construct "residue class specific" prime switches have been added. * The functions for loading the databases of rcwa groups and - mappings do no longer return the content of the respective database itself, but just the name of the variable which the database record is assigned to. Hence forgetting the ';;' at the end of the line when loading one of the databases does no longer result in megabytes of data printed to the screen. * Selector functions `All3CTs9Groups' and `All3CTs9Indices' have been added to the database of groups generated by 3 class transpositions interchanging residue classes with moduli <= 9. * The meaning of CT(P,Integers) has been changed in that 2 is no longer treated as a special case, and P is now the full prime set of the constructed group. -- That means e.g. that the former CT([],Integers) is now CT([2],Integers). * There is now a generating set for CT([2,3],Integers) consisting of only 6 class transpositions known, instead of 14 as before. Also, a generating set for CT([3],Integers) has been added. * A method for `ExtRepOfObj' for class transpositions has been added. This method returns the 4-tuple [r1,m1,r2,m2] corresponding to the interchanged residue classes r1(m1) and r2(m2).

- Update to new upstream release 4.3.1 * The propagation of the knowledge about bijectivity to inverses of bijective rcwa mappings is now taken care of by RCWA. -- Until GAP 4.8.1, this was done by the GAP Library.

- Update to new upstream release 4.0.0 * A database of groups generated by 3 class transpositions intechanging residue classes with moduli <= 9 has been added. For each of these 3031864 groups, the modulus and the order are stored. Also, for all finite ones among these groups, the length of the shortest respected partition is stored. * The following data has been added to the database of groups generated by 3 class transpositions: * data on subgroup- and supergroup relations between the groups in the database (lists 'subgroups' and 'supergroups'), * data on the orbit growth functions (list 'orbitgrowthtype'), * lists of lengths of short finite orbits of residue classes, and * data on sphere size cycles for orbits with periodic growth function. * RCWA makes now use of the new sparse representation of residue class unions implemented in ResClasses 4.0.0.

- Update to new upstream release 3.7.0 * An operation "MergerExtension" has been added. This operation constructs a certain infinite extension of a given transitive finite permutation group. * The manual section "Constructing residue-class-wise affine groups" has been revised. * The function "DrawOrbitPicture" has been improved, and in particular been made more efficient. The meaning of one of its arguments has changed. * Functions "EncryptIntoBitmapPicture" and "DecryptFromBitmapPicture" for steganography in bitmap pictures have been added. * A function "ShrinkMonochromePictureToGrayscalesPicture" has been added. This function is for producing smaller greyscale pictures from large monochrome pictures.

- Update to new upstream release 3.6.1 * Considerable additions to the database of groups generated by 3 class transpositions have been made * A database of pairs of class transpositions interchanging residue classes with moduli <= 12 sorted by the order of their product has been added. * A database similar to the one mentioned before up to modulus 32, but restricted to orders 8, 24, 40, 42, 84, 120, 168 and 420 has been added. * There is now an operation `Mirrored' which applies the automorphism conjugating with n |-> -n - 1 to an rcwa mapping of Z or an rcwa group over Z. This interchanges the action on negative and nonnegative integers. * A basic method for `RepresentativeAction' has been added which computes an rcwa permutation g such that G^g = H for given conjugate rcwa groups G, H < RCWA(Z). * A bug has been fixed which caused error messages when computing with rcwa mappings of Z in sparse representation which were not class-wise order-preserving.

- Split rcwa (version 3.5.1) off the gap RPM package