\Header{logical}{Logical Vectors}
\alias{as.logical}{logical}
\alias{as.logical.default}{logical}
\alias{is.logical}{logical}
\alias{TRUE}{logical}
\alias{FALSE}{logical}
\alias{T}{logical}
\alias{F}{logical}
\keyword{classes}{logical}
\keyword{logic}{logical}
\begin{Usage}
\begin{verbatim}
TRUE
FALSE
T; F

logical(length = 0)
as.logical(x)
is.logical(x)
\end{verbatim}
\end{Usage}
\begin{Description}
\texttt{TRUE} and \texttt{FALSE} are part of the \R\ language, where
\texttt{T} and \texttt{F} are global variables set to these.
All four are \texttt{logical(1)} vectors.

\texttt{logical} creates a logical vector of the specified length.
Each element of the vector is equal to \texttt{FALSE}.

\texttt{as.logical} attempts to coerce its argument to be of logical
type.

\texttt{is.logical} returns \texttt{TRUE} or \texttt{FALSE} depending on
whether its argument is of logical type or not.\end{Description}

