nlme (version 3.1-1)

formula.varFunc: Extract varFunc Formula

Description

This method function extracts the formula associated with a varFunc object, in which covariates and grouping factors are specified.

Usage

formula(object)

Arguments

object

an object inheriting from class varFunc, representing a variance function structure.

Value

• if object has a formula attribute, its value is returned; else NULL is returned.

Examples

formula(varPower(form = ~ fitted(.) | Sex))