nlme: getGroups.lme – R documentation

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getGroups.lme

Extract lme Object Groups

Description

The grouping factors corresponding to the linear mixed-effects model represented by object are extracted. If more than one level is indicated in level, the corresponding grouping factors are combined into a data frame; else the selected grouping factor is returned as a vector.

Usage

## S3 method for class 'lme'
getGroups(object, form, level, data, sep)

Arguments

`object`	an object inheriting from class `lme`, representing a fitted linear mixed-effects model.
`form`	this argument is included to make the method function compatible with the generic and is ignored in this method.
`level`	an optional integer vector giving the level(s) of grouping to be extracted from `object`. Defaults to the highest or innermost level of grouping.
`data`	unused
`sep`	character, the separator to use between group levels when multiple levels are collapsed. The default is `'/'`.

Value

either a data frame with columns given by the grouping factors indicated in level, or, when a single level is requested, a factor representing the selected grouping factor.

Author(s)

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

Examples

fm1 <- lme(pixel ~ day + day^2, Pixel,
  random = list(Dog = ~day, Side = ~1))
getGroups(fm1, level = 1:2)

nlme

Linear and Nonlinear Mixed Effects Models

v3.1-152

GPL (>= 2) | file LICENCE

Authors

José Pinheiro [aut] (S version), Douglas Bates [aut] (up to 2007), Saikat DebRoy [ctb] (up to 2002), Deepayan Sarkar [ctb] (up to 2005), EISPACK authors [ctb] (src/rs.f), Siem Heisterkamp [ctb] (Author fixed sigma), Bert Van Willigen [ctb] (Programmer fixed sigma), Johannes Ranke [ctb] (varConstProp()), R-core [aut, cre]

Initial release

2021-02-03