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MuMIn (version 1.15.6)

Formula manipulation: Manipulate model formulas

Description

simplify.formula rewrites a formula using shorthand notation. Currently only the factor crossing operator * is applied, so that expanded expression such as a+b+a:b becomes a*b. expand.formula does the opposite, additionally expanding other expressions, i.e. all nesting (/), grouping and ^.

Usage

simplify.formula(x)
expand.formula(x)

Arguments

x

a formula or an object from which it can be extracted (such as a fitted model object).

See Also

formula

delete.response, drop.terms, and reformulate

Examples

Run this code
# NOT RUN {
simplify.formula(y ~ a + b + a:b + (c + b)^2)
simplify.formula(y ~ a + b + a:b + 0)

expand.formula(~ a * b)

# }

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