Combining structs into one struct.

Hello, I have several structs that I would like to combine together into one. The issue I find is that the data for some reasons gets completely jumbled. Each time the file runs, the columns from one struct become a part of another and I cannot figure out why

CombineGLMParam('2_2_2', '2_3_2','2')

CombineGLMParam(0, '2_5_1','2')

function CombineGLMParam(bat1,bat2,bat)
%Combine GLM parameters by putting in the bat and the file. If bat1 is not 0, open the bat1 file and create a file GLM bat. 
% If it is 0, open the GLM Bat file and append the bat 2 file to GLM.

if bat1~=0
b1=load([dirf,'Bat_',bat1,'_GLM_Params.mat']);
b2=load([dirf,'Bat_',bat2,'_GLM_Params.mat']);
b1=struct2cell(b1)
b2=struct2cell(b2)

else
  b1=load([dirf,'GLM_',bat,'.mat']);
  b2=load([dirf,'Bat_',bat2,'_GLM_Params.mat']);

b1=struct2cell(b1.b4)
b2=struct2cell(b2)
end


 for n=1:size(b2,1)
    
    b3{n}=[b1{n}' b2{n}']';
    
 end

    
 Header={'ThetaX', 'ThetaY', 'ThetaZ', 'Td', 'Vd', 'Vw', 'Hd', 'Hw', 'Ld','Lw'};
 
b4=cell2struct(b3, Header, 2)

save([dirf,'GLM_',bat,'.mat'], 'b4')

[Stephen23]

I recommend avoiding struct2cell and cell2struct for this, because there is no guarantee about the existence or order of the structure fields. Just use fieldnames and loop over the fields:

https://www.mathworks.com/help/matlab/matlab_prog/generate-field-names-from-variables.html