\Header{addDate}{Add Periods to a Date}
\keyword{programming}{addDate}
\keyword{utilities}{addDate}
\keyword{ts}{addDate}
\keyword{chron}{addDate}
\begin{Description}\relax
Add periods to two element start date of given frequency to give a
new date. NULL periods is treated as 0.
\end{Description}
\begin{Usage}
\begin{verbatim}
    addDate(date, periods, freq)
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{date}] A two element date as used by tsp i.e c(year, period).
\item[\code{periods}] A number of periods.
\item[\code{freq}] The number of periods in a year.
\end{ldescription}
\end{Arguments}
\begin{Value}
A two element date.\end{Value}
\begin{Note}\relax
A useful utility not strictly part of tframe.
\end{Note}
\begin{SeeAlso}\relax
\code{\Link{tfExpand}}
\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
    addDate(c(1998,1), 20, 12)
\end{ExampleCode}
\end{Examples}

