getGroupsFormula: Extract Grouping Formula

Description Usage Arguments Value Author(s) See Also Examples

Description

The conditioning expression associated with formula(object) (i.e. the 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.

Usage

1
getGroupsFormula(object, asList, sep)

Arguments

object

any object from which a formula can be extracted.

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.

sep

character, the separator to use between group levels when multiple levels are collapsed. The default is '/'.

Value

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.

Author(s)

José Pinheiro and Douglas Bates [email protected]

See Also

getGroupsFormula.gls, getGroupsFormula.lmList, getGroupsFormula.lme, getGroupsFormula.reStruct, getGroups

Examples

1
getGroupsFormula(y ~ x | g1/g2)

Example output

~g1/g2
<environment: 0x282d958>

nlme documentation built on April 7, 2018, 5:03 p.m.

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