\name{stft}\title{Computes the Short Time Fourier Transform of a Vector}\usage{stft(X, win=min(80,floor(length(X)/10)), inc=min(24,floor(length(X)/30)), coef=64, wtype="hanning")}  \alias{stft}\arguments{\item{X}{The vector from which the stft is computed.}\item{win}{Length of the window. For long vectors the default windowsize is 80, for short vectors the window size is chosen so that 10windows fit in the vector.}\item{inc}{Increment by which the window is shifted. For long vectorsthe default increment is 24, for short vectors the increment is chosenso that 30 increments fit in the vector.} \item{coef}{Number of Fourier coefficients}\item{wtype}{Type of window used}}\description{This function computes the Short Time Fourier Transformof a given vector \code{X}. First, time-slices of length \code{win} areextracted from the vector. The shift of one time-slice to the next one isgiven by \code{inc}. The values of these time-slices are smoothed bymulitplying them with a window function specified in \code{wtype}. Forthe thus obtained windows, the Fast Fourier Transform is computed.}\value{Object of type stft. Contains the values of the stft andinformation about the parameters. \item{values}{A matrix containing the results of the stft. Each row ofthe matrix contains the \code{coef} Fourier coefficients of onewindow.} \item{windowsize}{The value of the parameter \code{win}}\item{increment}{The value of the parameter \code{inc}}\item{windowtype}{The value of the parameter \code{wtype}}}\author{Andreas Weingessel}\seealso{plot.stft}\examples{x<-rnorm(500)y<-stft(x)plot(y)}\keyword{ts}