% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/lfebd3.R
\name{lfbd.fr}
\alias{lfbd.fr}
\title{Generate a fractional 3-level LFBD}
\usage{
lfbd.fr(n, c)
}
\arguments{
\item{n}{Integer. Number of factors.}

\item{c}{Integer. Degree of fractionation, so the final number of runs is
`3^(n - c)`.}
}
\value{
An object of class `"lfbd_fr"` containing:
\describe{
  \item{design}{A data frame with run labels and treatment labels.}
  \item{design_matrix}{The reduced numeric design matrix.}
  \item{defining_contrasts}{Character vector of defining contrast labels.}
  \item{confounding_summary}{Data frame of main-effect and 2FI summaries.}
}
}
\description{
Constructs a fractional layout from the complete ternary design by repeated
fractional reduction and returns the design together with defining contrasts
and a low-order confounding summary.
}
\examples{
d <- lfbd.fr(2, 1)
d$design
d$defining_contrasts
}
\seealso{
[lfbd()], [lfbd.cf()], [lfbd_analyze()]
}
