The GAP 4 package `NumericalSgps' to compute with Numerical Semigroups ====================================================================== Introduction ------------ This is release 0.96 of the package `NumericalSgps'. The features of this package include - defining numerical semigroups; - computing several properties of numerical semigroups, namely: multiplicity, Frobenius number, (minimal) system of generators, Apéry set, gaps, fundamental gaps, etc.; - perform several operations on numerical semigroups, namely: intersection, quotient by an integer, decompose into irreducible semigroups, add a special gap; There is a manual in the sub-directory 'doc' written using the GAP package gapdoc which describes the available functions in detail. The dvi, pdf, html versions of the manual are also available there. If you have used this package, please let us know by sending us an email. If you have found important features missing or if there is a bug, we would appreciate it very much if you send us an email. Manuel Delgado <mdelgado@fc.up.pt> Pedro A. García-Sánchez <pedro@ugr.es> José Morais <josejoao@fc.up.pt> Contents -------- With this version you should have obtained the following files and directories: README this file EXAMPLES some examples doc the manual gap the GAP code init.g the file that initializes this package read.g the file that reads in the package PackageInfo.g information file for automatic processing version the version number Unpacking --------- You may get `NumericalSgps' as a compressed tar archive (file name ends with .tar.gz). Use the appropriate command on your system to unpack the archive. On UNIX systems the compressed tar archive may be unpacked by tar xzf numericalsgps-<version>.tar.gz or, if tar on your system does not understand the option z, by gunzip numericalsgps-<version>.tar.gz tar xf numericalsgps-<version>.tar which will in each case unpack the code into a directory 'numericalsgps' in the current directory. We assume that the current directory is the directory /usr/local/lib/gap4r4/pkg/. Installation ------------ You may have to start GAP with the -l option, for instance, gap -l "/usr/local/lib/gap4r4" Then try the following gap> LoadPackage( "numericalsgps" ); true gap> Good luck! If you use a LINUX system, you may have to, in order to save typing, write aliases: in the file `.bashrc' (or something equivalent, maybe with another syntax): alias gap='gap -l "/usr/local/lib/gap4r4;"' and in the file `.gaprc' LoadPackage( "numericalsgps" ); * Graphical Interface A graphical interface to define numerical semigroups is provided. For it to work you must have Tcl/Tk (http://www.tcl.tk/) installed. ---------- In other systems, there are equivalent ways to do the same.