% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/lfebd3.R
\name{reduce_once}
\alias{reduce_once}
\title{Reduce a design matrix by one factor of three}
\usage{
reduce_once(mat, type = c("fractional", "confounded"))
}
\arguments{
\item{mat}{Matrix to reduce.}

\item{type}{Character string specifying `"fractional"` or `"confounded"`.}
}
\value{
A reduced matrix with one-third as many rows as `mat` when reduction
  is possible.
}
\description{
Applies a single fractional or confounded reduction step to a design
matrix by selecting the first recursive pattern returned by
[build_triplet()].
}
\seealso{
[build_triplet()], [reduce_repeated()]
}
\keyword{internal}
