An object of class paired is a dataframe with two columns sharing the same class (usually numeric).
Arguments
Objects from the Class
Objects can be created by calls of the form new("paired", ...).
Extends
Class "data.frame", directly.
Class "list", by class "data.frame", distance 2.
Class "oldClass", by class "data.frame", distance 2.
Class "vector", by class "data.frame", distance 3.