Names.formula function

Extract Names from a formula

This method function returns the names of the terms corresponding to the right hand side of object (treated as a linear formula), obtained as the column names of the corresponding model.matrix.

## S3 method for class 'formula'
Names(object, data, exclude, ...)

Arguments

• object: an object inheriting from class "formula".
• data: an optional data frame containing the variables specified in object. By default the variables are taken from the environment from which Names.formula is called.
• exclude: an optional character vector with names to be excluded from the returned value. Default is c("pi",".").
• ...: some methods for this generic require additional arguments. None are used in this method.

Returns

a character vector with the column names of the model.matrix

corresponding to the right hand side of object which are not listed in excluded.

Author(s)

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

See Also

model.matrix, terms, Names

Examples

Names(distance ~ Sex * age, data = Orthodont)