A graphical interface

Here we describe a Tcl/Tk interface to specify numerical semigroups.

Graphical interface
This function pops up a Tcl/Tk window which allows the specification of numerical semigroups. The optional argument s is a numerical semigroup whose definition becomes displayed in the graphical interface.

The interface is very simple, it allows to specify a numerical semigroup by its generators or a (proportionally) modular numerical semigroup by its (proportionally) modular condition. The &GAP; variable by which the semigroup will be known must also be specified.

The interface also allows to apply some functions to the semigroup, namely , , , , and . Finally, it is also possible to add functions to this list and remove them. gap> s:=RandomNumericalSemigroup(3,9); <Numerical semigroup with 3 generators> gap> XNumericalSemigroup(s);

This would pop up the following window:

\begin{figure}[htbp] \begin{center} \leavevmode \includegraphics{xnumsgp} \end{center} \label{fig:xnumsgp} \end{figure}
<br><center><img src="xnumsgp.png"></center><br>