/* nag::ad::f07ca Passive Example Program.
*/
#include <dco.hpp>
#include <iostream>
#include <nagad.h>
// Function which calls NAG AD Library routines.
// Computes the solution to a system of linear equations Ax=b where A is a
// triagonal matrix of size n. Matrix A is stored in arrays l(n-1), d(n), u(n-1)
// that store the lower, the main and the upper diagonals.
template <typename T>
void func(std::vector<T> &l,
std::vector<T> &d,
std::vector<T> &u,
std::vector<T> &x);
int main()
{
std::cout << " nag::ad::f07ca Passive Example Program Results\n";
// Problem dimension
Integer n = 5;
// Matrix A stored in diagonals
std::vector<double> lv = {3.4, 3.6, 7.0, -6.0};
std::vector<double> dv = {3.0, 2.3, -5.0, -0.9, 7.1};
std::vector<double> uv = {2.1, -1.0, 1.9, 8.0};
// Right-hand-side vector b
std::vector<double> bv = {2.7, -0.5, 2.6, 0.6, 2.7};
// Computed solution to the system Ax=b
std::vector<double> xv(n);
// f07ca modifies rhs b and returns solution x into the same array
xv = bv;
// Call the NAG AD Lib functions
func(lv, dv, uv, xv);
std::cout << "\n Solution point = ";
for (int i = 0; i < n; i++)
{
std::cout.width(5);
std::cout << xv[i];
}
std::cout << std::endl;
return 0;
}
// Function which calls NAG AD Library routines.
template <typename T>
void func(std::vector<T> &l,
std::vector<T> &d,
std::vector<T> &u,
std::vector<T> &x)
{
Integer n = x.size(), nrhs = 1;
// Create AD configuration data object
Integer ifail = 0;
nag::ad::handle_t ad_handle;
// Solve the equations Ax = b for x
ifail = 0;
nag::ad::f07ca(ad_handle, n, nrhs, l.data(), d.data(), u.data(), x.data(), n,
ifail);
ifail = 0;
}