
244 R Programming for Bioinformatics
the right objects, where the names are unique within a set. There can be
any number of links b etween the left objects and the right objects, and these
can be thought of as edges. The edges can be tagged or named. Both the left
objects and the right objects can have named attributes associated with them.
In other words, a bimap is a bipartite graph and it represents the relationships
b etween two sets of identifiers. Bimaps can handle one-to-one relationships, as
well as one-to-many, and many-to-many relationships. Bimaps are represented
by the Bimap class. An example of a bimap would be to have probe IDs as
the