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# include <cppad/cppad.hpp>
namespace { // --------------------------------------------------------
// define the template function Test<VectorAD>(void) in empty namespace
template <class VectorAD>
bool Test(void)
{ bool ok = true;
using CppAD::AD;
using CppAD::NearEqual;
// domain space vector
size_t n = 2;
VectorAD X(n); // VectorAD is the template parameter in call to Test
X[0] = 0.;
X[1] = 1.;
// declare independent variables and start recording
// use the template parameter VectorAD for the vector type
CppAD::Independent(X);
AD<double> a = X[0] + X[1]; // first AD operation
AD<double> b = X[0] * X[1]; // second AD operation
// range space vector
size_t m = 2;
VectorAD Y(m); // VectorAD is the template paraemter in call to Test
Y[0] = a;
Y[1] = b;
// create f: X -> Y and stop tape recording
// use the template parameter VectorAD for the vector type
CppAD::ADFun<double> f(X, Y);
// check value
ok &= NearEqual(Y[0] , 1., 1e-10 , 1e-10);
ok &= NearEqual(Y[1] , 0., 1e-10 , 1e-10);
// compute f(1, 2)
CPPAD_TEST_VECTOR<double> x(n);
CPPAD_TEST_VECTOR<double> y(m);
x[0] = 1.;
x[1] = 2.;
y = f.Forward(0, x);
ok &= NearEqual(y[0] , 3., 1e-10 , 1e-10);
ok &= NearEqual(y[1] , 2., 1e-10 , 1e-10);
// compute partial of f w.r.t x[0] at (1, 2)
CPPAD_TEST_VECTOR<double> dx(n);
CPPAD_TEST_VECTOR<double> dy(m);
dx[0] = 1.;
dx[1] = 0.;
dy = f.Forward(1, dx);
ok &= NearEqual(dy[0] , 1., 1e-10 , 1e-10);
ok &= NearEqual(dy[1] , x[1], 1e-10 , 1e-10);
// compute partial of f w.r.t x[1] at (1, 2)
dx[0] = 0.;
dx[1] = 1.;
dy = f.Forward(1, dx);
ok &= NearEqual(dy[0] , 1., 1e-10 , 1e-10);
ok &= NearEqual(dy[1] , x[0], 1e-10 , 1e-10);
return ok;
}
} // End of empty namespace -------------------------------------------
# include <vector>
# include <valarray>
bool Independent(void)
{ bool ok = true;
typedef CppAD::AD<double> ADdouble;
// Run with VectorAD equal to three different cases
// all of which are Simple Vectors with elements of type AD<double>.
ok &= Test< CppAD::vector <ADdouble> >();
ok &= Test< std::vector <ADdouble> >();
ok &= Test< std::valarray <ADdouble> >();
return ok;
}