www.pudn.com > SPIHT_bandelet.rar > plot_geometry.m

function plot_geometry(theta, M, str) 
 
% plot_geometry - plot a geometry direction 
% 
%   plot_geometry(theta, M, str); 
% 
%   M should be a single dyadic square. 
%   str is the style for the geometry (default str='r'). 
% 
%   Copyright (c) 2005 Gabriel Peyré 
 
if nargin<2 
    M = []; 
end 
if nargin<3 
    str = 'r'; 
end 
 
hold on; 
 
if ~isempty(M); 
    n = size(M,1); 
    x = linspace(0,1,n); 
    imagesc(x,x,M); 
end 
 
pos = [0.5,0.5]; 
w = 1; 
x = pos(1) + w/2*[cos(theta), -cos(theta)]; 
y = pos(2) + w/2*[sin(theta), -sin(theta)]; 
plot(x,y, str); 
 
hold off;