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# include <FADBAD++/badiff.h>
# include <cppad/speed/det_by_minor.hpp>
# include <cppad/speed/uniform_01.hpp>
# include <cppad/vector.hpp>
bool compute_det_minor(
size_t size ,
size_t repeat ,
CppAD::vector<double> &matrix ,
CppAD::vector<double> &gradient )
{
// -----------------------------------------------------
// setup
// object for computing determinant
typedef B<double> ADScalar;
typedef CppAD::vector<ADScalar> ADVector;
CppAD::det_by_minor<ADScalar> Det(size);
size_t i; // temporary index
size_t m = 1; // number of dependent variables
size_t n = size * size; // number of independent variables
ADScalar detA; // AD value of the determinant
ADVector A(n); // AD version of matrix
// ------------------------------------------------------
while(repeat--)
{ // get the next matrix
CppAD::uniform_01(n, matrix);
// set independent variable values
for(i = 0; i < n; i++)
A[i] = matrix[i];
// compute the determinant
detA = Det(A);
// create function object f : A -> detA
detA.diff(0, m); // index 0 of m dependent variables
// evaluate and return gradient using reverse mode
for(i =0; i < n; i++)
gradient[i] = A[i].d(0); // partial detA w.r.t A[i]
}
// ---------------------------------------------------------
return true;
}