model.matrix
.# S3 method for formula
terms(x, specials = NULL, abb = NULL, data = NULL, neg.out = TRUE,
keep.order = FALSE, simplify = FALSE, …,
allowDotAsName = FALSE)
terms
object? A character vector or NULL
..
can be inferred. It is unused if there is no .
in
the formula.FALSE
the terms are reordered so
that main effects come first, followed by the interactions,
all second-order, all third-order and so on. Effects of a given
order are kept in the order specified..
in a formula refers to the
remaining variables contained in data
. Exceptionally,
.
can be treated as a name for non-standard uses of formulae.terms.object
object is returned. The object itself is
the re-ordered (unless keep.order = TRUE
) formula. In all
cases variables within an interaction term in the formula are
re-ordered by the ordering of the "variables"
attribute, which
is the order in which the variables occur in the formula.terms
, terms.object