MATLAB: Creating a loop with for loop

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How do you loop A11-A33 correctly?
function [determinant , inverse ] = invanddet3by3(A)
A11 =  invanddet2by2sol(A([2,3], [2,3])); % Cofactors 3x3 matrix A
A12 = -invanddet2by2sol(A([2,3], [1,3]));
A13 =  invanddet2by2sol(A([2,3], [1,2]));
A21 = -invanddet2by2sol(A([1,3], [2,3]));
A22 =  invanddet2by2sol(A([1,3], [1,3]));
A23 = -invanddet2by2sol(A([1,3], [1,2]));
A31 =  invanddet2by2sol(A([1,2], [2,3]));
A32 = -invanddet2by2sol(A([1,2], [1,3]));
A33 =  invanddet2by2sol(A([1,2], [1,2]));
D   = [A11 A12 A13; A21 A22 A23; A31 A32 A33]; % Adju Matrix
determinant = A(1,1) * A11 + A(1,2) * A12 + A(1,3) * A13; % Deter of A
if determinant == 0
    inverse=[];
else
    inverse = D' / determinant;  % Inv of A
end
end

Best Answer

solution: 
function [determinant , inverse ] = invanddet3by3(A)
D=zeros(3);
s=[2 3; 1 3; 1 2];
for k=1:size(D,1)
    for j=1:size(D,2)
        D(k,j)=(-2*mod(k+j,2)+1)*invanddet2by2sol(A(s(k,:),s(j,:)));
    end
end
determinant=sum(A(1,:).*D(1,:));
if determinant == 0
    inverse=[];
else
    inverse = D' / determinant;  % Inv of A
end
end
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