www.pudn.com > level_set_methods_1.1.zip > evolve_vector_ENO1.m, change:2005-05-05,size:674b


function [delta] = evolve_vector_ENO1(phi, dx, dy, u_ext, v_ext) 
% 
% Finds the amount of evolution under a vector field 
% based force and using 1st order accurate ENO scheme 
% 
% Author: Baris Sumengen  sumengen@ece.ucsb.edu 
% http://vision.ece.ucsb.edu/~sumengen/ 
% 
 
 
delta = zeros(size(phi)+2); 
data_ext = zeros(size(phi)+2); 
data_ext(2:end-1,2:end-1) = phi; 
% first scan the rows 
for i=1:size(phi,1) 
    delta(i+1,:) = delta(i+1,:) + upwind_ENO1(data_ext(i+1,:), u_ext(i+1,:), dx); 
end 
% then scan the columns 
for j=1:size(phi,2) 
    delta(:,j+1) = delta(:,j+1) + upwind_ENO1(data_ext(:,j+1), v_ext(:,j+1), dy); 
end 
delta = delta(2:end-1,2:end-1);