mexhat.tex

STFT相关函数

% This is part of the TFTB Reference Manual.
% Copyright (C) 1996 CNRS (France) and Rice University (US).
% See the file refguide.tex for copying conditions.



\markright{mexhat}
\hspace*{-1.6cm}{\Large \bf mexhat}

\vspace*{-.4cm}
\hspace*{-1.6cm}\rule[0in]{16.5cm}{.02cm}
\vspace*{.2cm}



{\bf \large \fontfamily{cmss}\selectfont Purpose}\\
\hspace*{1.5cm}
\begin{minipage}[t]{13.5cm}
Mexican hat wavelet in time domain.
\end{minipage}
\vspace*{.5cm}


{\bf \large \fontfamily{cmss}\selectfont Synopsis}\\
\hspace*{1.5cm}
\begin{minipage}[t]{13.5cm}
\begin{verbatim}
h = mexhat
h = mexhat(nu)
\end{verbatim}
\end{minipage}
\vspace*{.5cm}


{\bf \large \fontfamily{cmss}\selectfont Description}\\
\hspace*{1.5cm}
\begin{minipage}[t]{13.5cm}
        {\ty mexhat} returns the mexican hat wavelet, with central
        frequency {\ty nu} ({\ty nu} is a normalized frequency). Its
        expression writes
\[h(t)=\nu\ \frac{\sqrt{\pi}}{2}\ (1-2(\pi\nu t)^2)\ \exp[-(\pi\nu\ t)^2].\]

\hspace*{-.5cm}\begin{tabular*}{14cm}{p{1.5cm} p{8.5cm} c}
Name & Description & Default value\\
\hline
        {\ty nu} & any real between 0 and 0.5         & {\ty 0.05} \\
 \hline {\ty h}  & time vector containing the mexhat samples\\ 
                 & {\ty length(h)=2*ceil(1.5/nu)+1}\\
\hline
\end{tabular*}

\end{minipage}
\vspace*{1cm}


{\bf \large \fontfamily{cmss}\selectfont Example}
\begin{verbatim}
         plot(mexhat);
\end{verbatim}
\vspace*{.5cm}


{\bf \large \fontfamily{cmss}\selectfont See Also}\\
\hspace*{1.5cm}
\begin{minipage}[t]{13.5cm}
\begin{verbatim}
klauder.
\end{verbatim}
\end{minipage}