function?[tfrtf]?=?tfrstft（xtNhtrace）;?
%TFRSTFT?Short?time?Fourier?transform.?
%	[TFRTF]=TFRSTFT（XTNHTRACE）?computes?the?short-time?Fourier??
%	transform?of?a?discrete-time?signal?X.??
%??
%	X?????:?signal.?????
%	T?????:?time?instant（s）??±??±ê??????（default?:?1:length（X））.?
%	N?????:?number?of?frequency?bins??????¤???（default?:?length（X））.?
%??????????Sometimes?the?mark?‘Nf‘??instead?of?it.?
%	H?????:?frequency?smoothing?window?H?being?normalized?so?as?to?
%	???be??of?unit?energy.????????????????????°（default?:?Hamming（N/4））.?
%?????Sometimes?it?is?designated?as?Lh?parameter.?
%	TRACE?:?if?nonzero?the?progression?of?the?algorithm?is?shown?
%	?????????????????????????????????（default?:?0）.?
%	TFR???:?time-frequency?decomposition?（complex?values）.?The?
%?frequency?axis?is?graduated?from?-0.5?to?0.5.stft±??????
%	F?????:?vector?of?normalized?frequencies.?é?????????ò???
%?
%	Example?:?
%	?sig=[fmconst（1280.2）;fmconst（1280.4）];?tfr=tfrstft（sig）;?
%	?subplot（211）;?imagesc（abs（tfr））;?
%	?subplot（212）;?imagesc（angle（tfr））;?
%??
%	See?also?all?the?time-frequency?representations?listed?in?
%	?the?file?CONTENTS?（TFR*）?
?
%	F.?Auger?May-August?1994?July?1995.?
%	Copyright?（c）?1996?by?CNRS?（France）.?
%?
%	-------------------?CONFIDENTIAL?PROGRAM?--------------------??
%	This?program?can?not?be?used?without?the?authorization?of?its?
%	author（s）.?For?any?comment?or?bug?report?please?send?e-mail?to??
%	f.auger@ieee.org??
?
[xrowxcol]?=?size（x）;%·?±???????????????x?is?vector?in?row;?
if?（nargin??error（‘At?least?1?parameter?is?required‘）;