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CaGe V0.3


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 bond 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 number of 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.