

    \filetitle{bpass}{Band-pass filter}{tseries/bpass}

	\paragraph{Syntax}
 
 \begin{verbatim}
 [X,T] = bpass(X,BAND,RANGE,...)
 \end{verbatim}
 \paragraph{Output arguments}
 
 \begin{itemize}
 \item
   \texttt{X} {[} tseries {]} - Band-pass filtered tseries object.
 \item
   \texttt{T} {[} tseries {]} - Estimated trend tseries object.
 \end{itemize}
 \paragraph{Input arguments}
 
 \begin{itemize}
 \item
   \texttt{X} {[} tseries {]} - Input tseries object that will be
   filtered.
 \item
   \texttt{RANGE} {[} numeric \textbar{} Inf {]} Date range on which the
   data will be filtered.
 \item
   \texttt{BAND} {[} numeric {]} - Band of periodicities to be retained
   in the output data, \texttt{BAND = {[}LOW,HIGH{]}}.
 \end{itemize}
 \paragraph{Options}
 
 \begin{itemize}
 \item
   \texttt{'addTrend='} {[} \emph{\texttt{true}} \textbar{}
   \texttt{false} {]} - Add the estimated linear time trend back to
   filtered output series if \texttt{band} includes Inf.
 \item
   \texttt{'detrend='} {[} \emph{\texttt{true}} \textbar{} \texttt{false}
   {]} - Remove an estimated time trend from the data before filtering.
 \item
   \texttt{'log='} {[} \texttt{true} \textbar{} \emph{\texttt{false}} {]}
   - Logarithmise the data before filtering, de-logarithmise afterwards.
 \item
   \texttt{'method='} {[} \emph{\texttt{'cf'}} \textbar{}
   \texttt{'hwfsf'} {]} - Type of band-pass filter:
   Christiano-Fitzgerald, or h-windowed frequency-selective filter.
 \item
   \texttt{'unitRoot='} {[} \emph{\texttt{true}} \textbar{}
   \texttt{false} {]} - Assume unit root in the input data.
 \end{itemize}
 See help on \url{tseries/trend} for other options available when
 \texttt{'detrend='} is set to true.
 
 \paragraph{Description}
 
 Christiano, L.J. and T.J.Fitzgerald (2003). The Band Pass Filter.
 International Economic Review, 44(2), 435---465.
 
 Iacobucci, A. \& A. Noullez (2005). A Frequency Selective Filter for
 Short-Length Time Series. Computational Economics, 25, 75---102.
 
 \paragraph{Example}


