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Introduction
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The aim of this package is to turn
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It requires the usage of external programs as is the case of
<C>graphviz</C> <Cite Key="KoutsofiosNorth:2002"/>, a software for drawing graphs developed at AT
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T Labs, that can be obtained at
<URL>http://www.graphviz.org/</URL>.
It is used not only to draw right Cayley graphs of finite semigroups and Schüzenberger graphs of finite inverse semigroups but also to visualise in the usual way the egg-box picture of a D-classe of a finite semigroup.
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<B>Important note</B>: The version of <C>graphviz</C> to install must be
greater or equal to 1.16.
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Tcl/Tk should also be available in order to run the graphical interfaces
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XAutomaton and XSemigroup
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used to specify automata and semigroups.
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<B>Warning</B>: the use of XAutomaton and XSemigroup is intended only for simple examples. After its use one may have to start another GAP session.
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