[eigen] Adjoint

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I am trying to compute the adjoint of a matrix, but Eigen 3.0.5 gives me a result I am not expecting. To illustrate this, I reduced the issue to the attached code. I understand "adjoint" as the traspose of the cofactor matrix. In the attached example, the adjoint would be (checked with Maple):

-3   6   -3
6  -12   6
-3   6   -3

But Eigen gives me the transpose of my input matrix:

1 4 7
2 5 8
3 6 9

So the question is, does Eigen use another definition for adjoint, am I making a mistake in my code or is this a bug?

Thanks in advance for your answer,


#include <iostream>
#include <Eigen/Eigen>

int main(){
        Eigen::Matrix<double,Eigen::Dynamic,Eigen::Dynamic> m(3,3);
        m(0,0)=1; m(0,1)=2; m(0,2)=3;
        m(1,0)=4; m(1,1)=5; m(1,2)=6;
        m(2,0)=7; m(2,1)=8; m(2,2)=9;
        return 0;

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