pi314.cc

#include <kv/kraw-approx.hpp>
#include <kv/defint.hpp>

namespace ub = boost::numeric::ublas;

typedef kv::interval<double> itv;

struct Func {
	template <class T> ub::vector<T> operator() (const ub::vector<T>& x) {
		static T p = kv::constants<T>::pi();
		static T c1 = kv::constants<T>::str("3.14");
		ub::vector<T> y(1);
		y(0) = p * x(0) * sin(11 / x(0)) - 11 * c1;
		return y;
	}
};

template <class TT>
struct Func2 {
	TT r;

	Func2(TT r) : r(r) {}

	template <class T> T operator() (const T& x) {
		static T p = kv::constants<T>::pi();
		return 2 * p * r * sin(x / r);
	}
};

int main()
{
	ub::vector<itv> ix;
	ub::vector<itv::base_type> x;
	bool b;

	std::cout.precision(12);

	x.resize(1);
	ix.resize(1);

	x(0) = 200.;

	b = kv::krawczyk_approx(Func(), x, ix, 5, false);
	if (b == false) {
		std::cout << "fail\n";
		return 1;
	} else {
		std::cout << ix(0) << "\n";
	}
	
	std::cout << kv::defint_autostep(Func2<itv>(ix(0)), itv(0), itv(11), 12) << "\n";
}