\HeaderA{extendLength}{Extend the length of a signal or matrix}{extendLength}
\keyword{methods}{extendLength}
\begin{Description}\relax
Extend the length of a signal or matrix by row
\end{Description}
\begin{Usage}
\begin{verbatim}
extendLength(x, addLength = NULL, method = c("reflection", "open", "circular"), direction = c("right", "left", "both"))
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{x}] a vector or matrix with column with each column as a signal 
\item[\code{addLength}] the length to be extended 
\item[\code{method}] three methods available, c("reflection", "open", "circular"). By default, it is "reflection". 
\item[\code{direction}] three options available: c("right", "left", "both") 
\end{ldescription}
\end{Arguments}
\begin{Value}
return the extended vector or matrix.
\end{Value}
\begin{Author}\relax
Pan Du
\end{Author}
\begin{SeeAlso}\relax
\code{\LinkA{extendNBase}{extendNBase}}
\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
        # a = matrix(rnorm(9), 3)
        # extendLength(a, 3, direction='right')         ## not exposed function
\end{ExampleCode}
\end{Examples}

