is_factor_term: Is a model term a factor (categorical)?

In gratia: Graceful 'ggplot'-Based Graphics and Other Functions for GAMs Fitted Using 'mgcv'

Is a model term a factor (categorical)?

Description

Given the name (a term label) of a term in a model, identify if the term is a factor term or numeric. This is useful when considering interactions, where terms like fac1:fac2 or num1:fac1 may be requested by the user. Only for terms of the type fac1:fac2 will this function return TRUE.

Usage

is_factor_term(object, term, ...)

## S3 method for class 'terms'
is_factor_term(object, term, ...)

## S3 method for class 'gam'
is_factor_term(object, term, ...)

## S3 method for class 'bam'
is_factor_term(object, term, ...)

## S3 method for class 'gamm'
is_factor_term(object, term, ...)

## S3 method for class 'list'
is_factor_term(object, term, ...)

Arguments

object	an R object on which method dispatch is performed
term	character; the name of a model term, in the sense of attr(terms(object), "term.labels"). Currently not checked to see if the term exists in the model.
...	arguments passed to other methods.

Value

A logical: TRUE if and only if all variables involved in the term are factors, otherwise FALSE.

gratia documentation built on April 3, 2025, 11:42 p.m.