.\" -*- nroff -*- generated from .Rd format
.BG
.FN getGroupsFormula
.TL
Extract Grouping Formula
.DN
The conditioning expression associated with `formula(object)'
(i.e. an expression after the `|' operator) is returned either as
a named list of one-sided formulas, or a single one-sided formula,
depending  on the value of `asList'. The components of the
returned list are ordered from outermost to innermost level and are
named after the grouping factor expression.
.CS
getGroupsFormula(object, asList)
.RA
.AG object
any object from which a formula can be extracted.
.OA
.AG asList
an optional logical value. If `TRUE' the returned
value with be a list of formulas; else, if `FALSE' the returned
value will be a one-sided formula. Defaults to `FALSE'.
.RT
a one-sided formula, or a list of one-sided formulas, with the
grouping structure associated with `formula(object)'. If no
conditioning expression is present in `formula(object)' a
`NULL' value is returned.

.SA
`getGroupsFormula.gls',
`getGroupsFormula.lmList',
`getGroupsFormula.lme',
`getGroupsFormula.reStruct',
`getGroups'
.EX
getGroupsFormula(y ~ x | g1/g2)
.KW models
.WR
