chooseelements.m

MATLAB二维电阻抗断层成像算法!用于医学成像,里面包括有限元剖分正问题,及反问题的算法.并且附有网络剖分数据表!

function Ind=ChooseElements(Node,Element,E,N);

%ChooseElements Lets you to choose an inhomogeneity (a set of elements) for 2D EIT simulations
% Function Ind=ChooseElemenst(Node,Element,E,N);
% lets you choose N elements from a mesh defined by Element.If N is not given, as many
% elements as you want are chosen. Ind are the indices to the Element topolgy.
%
% INPUT
% Node = node information
% Element = element information
% E = electrode information (elements under the electrodes, optional, use [] if not defined)
% N = the number of elements to be chosen (optional)
%
% OUTPUT
% Ind = Indices of the chosen elements

Nod=reshape([Node.Coordinate]',2,max(size(Node)))'; %剖分节点坐标
Topol=reshape([Element.Topology]',size(Element(1).Topology,2),max(size(Element)))';
%剖分拓朴结构
clf,plcigrid(Nod,Topol,E,'r'),axis equal;          %图示剖分
hold on
if nargin==4      %如果有确定的单元指定个数6
 Ind=zeros(N,1);
 for ii=1:N
  [x,y]=ginput(1);    %指定单元 
  Ind(ii)=tsearch(Nod(:,1),Nod(:,2),Topol,x,y);
  Hii=Nod(Topol(Ind(ii),:),:);
  patch(Hii(:,1),Hii(:,2),1);            
 end
else
  Ind=[];
  [x,y]=ginput;
  Ind=[Ind;tsearch(Nod(:,1),Nod(:,2),Topol,x,y)];
 for ii=1:max(size(Ind))
  Hii=Nod(Topol(Ind(ii),:),:);
  patch(Hii(:,1),Hii(:,2),1);           
 end
end