Update varFunc Object

update.varFunc {nlme}

R Documentation

Update varFunc Object

Description

If the formula(object) includes a "." term, representing a fitted object, the variance covariate needs to be updated upon completion of an optimization cycle (in which the variance function weights are kept fixed). This method function allows a reevaluation of the variance covariate using the current fitted object and, optionally, other variables in the original data.

Usage

## S3 method for class 'varFunc'
update(object, data, ...)

Arguments

`object`	an object inheriting from class `"varFunc"`, representing a variance function structure.
`data`	a list with a component named `"."` with the current version of the fitted object (from which fitted values, coefficients, and residuals can be extracted) and, if necessary, other variables used to evaluate the variance covariate(s).
`...`	some methods for this generic require additional arguments. None are used in this method.

Value

if formula(object) includes a "." term, an varFunc object similar to object, but with the variance covariate reevaluated at the current fitted object value; else object is returned unchanged.

Author(s)

José Pinheiro and Douglas Bates bates@stat.wisc.edu