$\newcommand{\W}[1]{ \; #1 \; } \newcommand{\R}[1]{ {\rm #1} } \newcommand{\B}[1]{ {\bf #1} } \newcommand{\D}[2]{ \frac{\partial #1}{\partial #2} } \newcommand{\DD}[3]{ \frac{\partial^2 #1}{\partial #2 \partial #3} } \newcommand{\Dpow}[2]{ \frac{\partial^{#1}}{\partial {#2}^{#1}} } \newcommand{\dpow}[2]{ \frac{ {\rm d}^{#1}}{{\rm d}\, {#2}^{#1}} }$
# include <vector> # include <cstddef> # include <cppad/speed/det_of_minor.hpp> bool det_of_minor() { bool ok = true; size_t i; // dimension of the matrix A size_t m = 3; // index vectors set so minor is the entire matrix A std::vector<size_t> r(m + 1); std::vector<size_t> c(m + 1); for(i= 0; i < m; i++) { r[i] = i+1; c[i] = i+1; } r[m] = 0; c[m] = 0; // values in the matrix A double data[] = { 1., 2., 3., 3., 2., 1., 2., 1., 2. }; // construct vector a with the values of the matrix A std::vector<double> a(data, data + 9); // evaluate the determinant of A size_t n = m; // minor has same dimension as A double det = CppAD::det_of_minor(a, m, n, r, c); // check the value of the determinant of A ok &= (det == (double) (1*(2*2-1*1) - 2*(3*2-1*2) + 3*(3*1-2*2)) ); // minor where row 0 and column 1 are removed r[m] = 1; // skip row index 0 by starting at row index 1 c[0] = 2; // skip column index 1 by pointing from index 0 to index 2 // evaluate determinant of the minor n = m - 1; // dimension of the minor det = CppAD::det_of_minor(a, m, m-1, r, c); // check the value of the determinant of the minor ok &= (det == (double) (3*2-1*2) ); return ok; }