www.pudn.com > TimeFrequency.rar > MakeWindow.m

function win=MakeWindow(Name,n) 
% MakeWindow -- Make artificial Window 
%  Usage 
%    wig = MakeWindow(Name,n) 
%  Inputs 
%    Name   string: 'Rectangle', 'Hanning', 'Hamming', 
%            'Gaussian', 'Blackman'; 
%    n      desired half Window length 
%  Outputs 
%    win    1-d Window, with length 2n+1; 
%  Description 
%    Rectangle		1 
%    Hanning 		cos(pi*t)^2 
%    Hamming		.54 + .46cos(2pi*t) 
%    Gaussian		exp(-18 * t^2/2) 
%    Blackman		.42 + .50*cos(2pi*t) + .08cos(4.*pi.*t) 
%  Examples 
%     win = MakeWindow('Rectangle',17);	plot(win); 
%     win = MakeWindow('Hanning',  17);	plot(win); 
%     win = MakeWindow('Hamming',  17);	plot(win); 
%     win = MakeWindow('Gaussian', 17);	plot(win);  
%     win = MakeWindow('Blackman', 17);	plot(win); 
%  See Also 
% 
%  Algorithm 
%    Easy to implement. 
%  References 
%    Mallat, "A Wavelet Tour of Signal Processing"; 4.2.2 Choice of Window. 
% 
 t = ((1:(2*n+1))-(n+1))./n./2; 
 
 if strcmp(Name,'Rectangle'), 
 	win = ones(size(t)); 
 elseif strcmp(Name,'Hanning'), 
	win = realpow(cos(pi.*t),2); 
 elseif strcmp(Name,'Hamming'), 
	win = .54 + .46*cos(2.*pi.*t); 
 elseif strcmp(Name,'Gaussian'), 
	win = exp(-realpow(t,2)*18); 
 elseif strcmp(Name,'Blackman'), 
	win = .42 + .50*cos(2.*pi.*t) + .08*cos(4.*pi.*t); 
 end; 
 
% 
  
 
% 
% Copyright (c) 1996. Xiaoming Huo 
%  
% Modified by Maureen Clerc and Jerome Kalifa, 1997 
% clerc@cmapx.polytechnique.fr, kalifa@cmapx.polytechnique.fr 
     
     
%    
% Part of WaveLab Version 802 
% Built Sunday, October 3, 1999 8:52:27 AM 
% This is Copyrighted Material 
% For Copying permissions see COPYING.m 
% Comments? e-mail wavelab@stat.stanford.edu 
%