relations (version 0.2-0)

classes: Relation Equivalence Classes

Description

Provide class ids (classes) for an equivalence relation, or the indifference relation of a weak order.

Usage

relation_class_ids(x)
relation_classes(x)

Arguments

x

an object inheriting from class relation.

Value

• For relation_class_ids, a numeric vector with class ids corresponding to the classes of the equivalence relation, or the indifference relation of the weak order with ids ordered according to increasing preference. For relation_classes, an object of class "relation_classes_of_objects", which is a named list of character vectors, where the list components correspond to the classes, the component names to the class ids, and each character vector to the object labels of each class.

Examples

## Equivalence.
f <- factor(rep(c("Good", "Bad", "Ugly"), c(3, 2, 1)))
R <- as.relation(f)
relation_is_equivalence(R)
table(ids = relation_class_ids(R), orig = f)

relation_classes(R)

## Weak order ("weak preference").
f <- ordered(f, levels = c("Ugly", "Bad", "Good"))
R <- as.relation(f)
relation_is_weak_order(R)
table(ids = relation_class_ids(R), orig = f)

relation_classes(R)