label.m

来自「C++编译指导」· M 代码 · 共 23 行

function elem = label(node,elem)
% LABEL label the longest edge of each triangle as the base
% 
% elem = label(node,elem)
%
% Input:
%  node: coordinates of nodes
%  elem: element array
%
% Output:
%  elem: elem(t,1) is opposite to the longest edge
%
% L. Chen 3-26-2006

edgelength(:,1) = (node(elem(:,3),1)-node(elem(:,2),1)).^2 ...
                + (node(elem(:,3),2)-node(elem(:,2),2)).^2;
edgelength(:,2) = (node(elem(:,1),1)-node(elem(:,3),1)).^2 ...
                + (node(elem(:,1),2)-node(elem(:,3),2)).^2;
edgelength(:,3) = (node(elem(:,3),1)-node(elem(:,2),1)).^2 ...
                + (node(elem(:,3),2)-node(elem(:,2),2)).^2;
[temp,I] = max(edgelength,[],2);
elem((I==2),[1 2 3]) = elem((I==2), [2 3 1]);
elem((I==3),[1 2 3]) = elem((I==3), [3 1 2]);