%Create 2D model using EIDORS of matlab.

I am using EIDORS. I want to create thousands of images using for loop just by changing the position and conductivity of the object. But its not working.

Nel=16;
stim=mk_stim_patterns(Nel,1,'{ad}','{ad}',{'no_meas_current'},0.01);
%Create 2D model
 my1=[0.01,0.015,0.02];
 my2=0.02;
 for i=1:length(my1)
extra ={'ball','solid ball = cylinder(-0.02,0.02,0.02;-0.025,0.025,1.2;my2) and orthobrick(-1,-1,0;1,1,0.05);'}; 
extra ={'ball','solid ball = cylinder(-0.02,0.02,0.02;-0.025,0.025,1.2;my1(i)) and orthobrick(-1,-1,0;1,1,0.05);'};
fmdl= ng_mk_cyl_models([0,0.06,0.006],[16],[0.0065,0,0.001],extra); fmdl.stimulation= stim; img2 = mk_image(fmdl,7*10^-3); img2.elem_data(fmdl.mat_idx{2})=10^-16; img2.elem_data(fmdl.mat_idx{2})=5.96*10^7; vi = fwd_solve(img2); vi.meas figure %subplot(232) show_fem(img2,[1,1]); 
end

[Jan]

Please explain "But its not working" with any details.

[Jiaxiang]

Note mat_idx does not work in 2D. Netgen does not provide it.

Answer 1

[Rishav]

Hi priya,

To correctly interpolate 'my1(i)' into the string defining your object, you will need to use string concatenation or 'sprintf' for constructing the string with the variable value.

Please refer to the code below to know how you can modify your loop to correctly change the position or property of the object:

Nel = 16;
stim = mk_stim_patterns(Nel, 1, '{ad}', '{ad}', {'no_meas_current'}, 0.01);

% Conductivity values
my1 = [0.01, 0.015, 0.02];
my2 = 0.02;

for i = 1:length(my1)
    % Construct the extra definition string with my1(i) using sprintf
    extra_def = sprintf('ball','solid ball = cylinder(-0.02,0.02,0.02;-0.025,0.025,1.2;%f) and orthobrick(-1,-1,0;1,1,0.05);', my1(i));
    extra = {'ball', extra_def};

    % Create 2D model
    fmdl = ng_mk_cyl_models([0, 0.06, 0.006], [16], [0.0065, 0, 0.001], extra);
    fmdl.stimulation = stim;
    
    img2 = mk_image(fmdl, 7*10^-3);
    
    % Since mat_idx does not work in 2D, you might need to manually identify 
    % the elements that belong to your object and set their conductivity
    % This part of the code would need customization based on your object's location
    
    img2.elem_data(:) = 10^-16; % Background conductivity
    % You need to define how to select elements for the object
    % For example, if you had a way to identify the object's elements, it might look like:
    % obj_elems = find_object_elements(fmdl, ...); % This is a placeholder for actual logic
    % img2.elem_data(obj_elems) = 5.96*10^7; % Object conductivity
    
    vi = fwd_solve(img2);
    figure; show_fem(img2, [1, 1]);
end