R: A function to construct a terms object from a formula.

This help topic is for R version 1.5.0. For the current version of R, try https://stat.ethz.ch/R-manual/R-patched/library/base/html/terms.formula.html

terms.formula {base}

R Documentation

A function to construct a terms object from a formula.

Description

This function takes a formula and some optional arguments and constructs a terms object. The terms object can then be used to construct a model.matrix.

Usage

terms.formula(x, specials=NULL, abb=NULL, data=NULL, neg.out=TRUE,
              keep.order=FALSE, ...)

Arguments

`x`	A formula.
`specials`	What functions in the formula should be marked as special in the terms object.
`abb`	Unused in R.
`data`	A data frame from which the meaning of the special symbol `.` can be inferred. It is unused if there is no `.` in the formula.
`neg.out`	`TRUE` if terms with a minus, `-` should be removed. If FALSE these are kept in and indicate a negative order (for fractionate?).
`keep.order`	A logical value indicating whether the terms should keep their positions. If FALSE the terms are reordered so that main effects come first.
`...`	further arguments passed to or from other methods.

Details

Not all of the options work in the same way that they do in S and not all are implemented.

Value