www.pudn.com > level_set_methods_1.1.zip > evolve_vector_ENO2.m, change:2005-05-05,size:672b


function [delta] = evolve_vector_ENO2(phi, dx, dy, u_ext, v_ext) 
% 
% Finds the amount of evolution under a vector field 
% based force and using 2nd order accurate ENO scheme 
% 
% Author: Baris Sumengen  sumengen@ece.ucsb.edu 
% http://vision.ece.ucsb.edu/~sumengen/ 
% 
 
delta = zeros(size(phi)+4); 
data_ext = zeros(size(phi)+4); 
data_ext(3:end-2,3:end-2) = phi; 
% first scan the rows 
for i=1:size(phi,1) 
    delta(i+2,:) = delta(i+2,:) + upwind_ENO2(data_ext(i+2,:), u_ext(i+2,:), dx); 
end 
% then scan the columns 
for j=1:size(phi,2) 
    delta(:,j+2) = delta(:,j+2) + upwind_ENO2(data_ext(:,j+2), v_ext(:,j+2), dy); 
end 
delta = delta(3:end-2,3:end-2);