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CaGe (Carbon Generator) is a computer program which takes the output of
some graph generation program as input and provides several output
styles, especially graphical output. Windows, buttons etc. are used to
interact with CaGe. CaGe is based on Tcl/Tk and
thus behaves like typical Tcl/Tk--applications. Since the generated graphs
can be interpreted as molecules, CaGe is interesting not only for
graph theorists, but especially for chemists.
Since chemists use a rather different terminology than graph theorists, here
is a short list of correspondences: An atom in chemistry is
represented by a vertex in graph theory. The same way, a
between two atoms is represented by an edge.
A double or triple bond is only represented by a single edge. A vertex is
adjacent to another vertex if they are connected by an edge.
So, if two vertices are adjacent to each other, this means that (considered
as atoms) they have bonds. The valence of a vertex is the
adjacent vertices. Since the vertex is interpreted as an atom, it is the
number of other atoms it has bonds with, but not the number of bonds itself.
E.g. for a carbon atom, the valence is
not always 4: Double bonds are considered as one adjacency.
A graph (sometimes a graph is also called map)
corresponds to a molecule. A graph is
x--regular if every vertex is x--valent. So this means that
every atom has bonds to exactly x other atoms.