int main(int argc, char **argv)
{
double pi = std::atan(1.0)*4.0;
// Values of function arguments
double a = pi/4;
double b = 2.0;
double c = 3.0;
// Rad objects
Sacado::Rad::ADvar<double> arad = a;
Sacado::Rad::ADvar<double> brad = b;
Sacado::Rad::ADvar<double> crad = c; // Passive variable
Sacado::Rad::ADvar<double> rrad; // Result
// Compute function
double r = func(a, b, c);
// Compute derivative analytically
double drda, drdb;
func_deriv(a, b, c, drda, drdb);
// Compute function and derivative with AD
rrad = func(arad, brad, crad);
Sacado::Rad::ADvar<double>::Gradcomp();
// Extract value and derivatives
double r_ad = rrad.val(); // r
double drda_ad = arad.adj(); // dr/da
double drdb_ad = brad.adj(); // dr/db
// Print the results
int p = 4;
int w = p+7;
std::cout.setf(std::ios::scientific);
std::cout.precision(p);
std::cout << " r = " << r << " (original) == " << std::setw(w) << r_ad
<< " (AD) Error = " << std::setw(w) << r - r_ad << std::endl
<< "dr/da = " << std::setw(w) << drda << " (analytic) == "
<< std::setw(w) << drda_ad << " (AD) Error = " << std::setw(w)
<< drda - drda_ad << std::endl
<< "dr/db = " << std::setw(w) << drdb << " (analytic) == "
<< std::setw(w) << drdb_ad << " (AD) Error = " << std::setw(w)
<< drdb - drdb_ad << std::endl;
double tol = 1.0e-14;
if (std::fabs(r - r_ad) < tol &&
std::fabs(drda - drda_ad) < tol &&
std::fabs(drdb - drdb_ad) < tol) {
std::cout << "\nExample passed!" << std::endl;
return 0;
}
else {
std::cout <<"\nSomething is wrong, example failed!" << std::endl;
return 1;
}
}
int main(int argc, char **argv)
{
double pi = std::atan(1.0)*4.0;
// Values of function arguments
double a = pi/4;
double b = 2.0;
double c = 3.0;
// Number of independent variables
int num_deriv = 2;
// Fad objects
Sacado::Rad::ADvar< Sacado::Fad::DFad<double> > arad =
Sacado::Fad::DFad<double>(num_deriv, 0, a);
Sacado::Rad::ADvar< Sacado::Fad::DFad<double> > brad =
Sacado::Fad::DFad<double>(num_deriv, 1, b);
Sacado::Rad::ADvar< Sacado::Fad::DFad<double> > crad = c;
Sacado::Rad::ADvar< Sacado::Fad::DFad<double> > rrad;
// Compute function
double r = func(a, b, c);
// Compute derivative analytically
double drda, drdb;
func_deriv(a, b, c, drda, drdb);
// Compute second derivative analytically
double d2rda2, d2rdb2, d2rdadb;
func_deriv2(a, b, c, d2rda2, d2rdb2, d2rdadb);
// Compute function and derivative with AD
rrad = func(arad, brad, crad);
Sacado::Rad::ADvar< Sacado::Fad::DFad<double> >::Gradcomp();
// Extract value and derivatives
double r_ad = rrad.val().val(); // r
double drda_ad = arad.adj().val(); // dr/da
double drdb_ad = brad.adj().val(); // dr/db
double d2rda2_ad = arad.adj().dx(0); // d^2r/da^2
double d2rdadb_ad = arad.adj().dx(1); // d^2r/dadb
double d2rdbda_ad = brad.adj().dx(0); // d^2r/dbda
double d2rdb2_ad = brad.adj().dx(1); // d^2/db^2
// Print the results
int p = 4;
int w = p+7;
std::cout.setf(std::ios::scientific);
std::cout.precision(p);
std::cout << " r = " << std::setw(w) << r << " (original) == "
<< std::setw(w) << r_ad << " (AD) Error = " << std::setw(w)
<< r - r_ad << std::endl
<< " dr/da = " << std::setw(w) << drda << " (analytic) == "
<< std::setw(w) << drda_ad << " (AD) Error = " << std::setw(w)
<< drda - drda_ad << std::endl
<< " dr/db = " << std::setw(w) << drdb << " (analytic) == "
<< std::setw(w) << drdb_ad << " (AD) Error = " << std::setw(w)
<< drdb - drdb_ad << std::endl
<< "d^2r/da^2 = " << std::setw(w) << d2rda2 << " (analytic) == "
<< std::setw(w) << d2rda2_ad << " (AD) Error = " << std::setw(w)
<< d2rda2 - d2rda2_ad << std::endl
<< "d^2r/db^2 = " << std::setw(w) << d2rdb2 << " (analytic) == "
<< std::setw(w) << d2rdb2_ad << " (AD) Error = " << std::setw(w)
<< d2rdb2 - d2rdb2_ad << std::endl
<< "d^2r/dadb = " << std::setw(w) << d2rdadb << " (analytic) == "
<< std::setw(w) << d2rdadb_ad << " (AD) Error = " << std::setw(w)
<< d2rdadb - d2rdadb_ad << std::endl
<< "d^2r/dbda = " << std::setw(w) << d2rdadb << " (analytic) == "
<< std::setw(w) << d2rdbda_ad << " (AD) Error = " << std::setw(w)
<< d2rdadb - d2rdbda_ad << std::endl;
double tol = 1.0e-14;
if (std::fabs(r - r_ad) < tol &&
std::fabs(drda - drda_ad) < tol &&
std::fabs(drdb - drdb_ad) < tol &&
std::fabs(d2rda2 - d2rda2_ad) < tol &&
std::fabs(d2rdb2 - d2rdb2_ad) < tol &&
std::fabs(d2rdadb - d2rdadb_ad) < tol) {
std::cout << "\nExample passed!" << std::endl;
return 0;
}
else {
std::cout <<"\nSomething is wrong, example failed!" << std::endl;
return 1;
}
}