test_vector.cpp

#include <iostream>
#include <shogun/base/init.h>
#include <shogun/lib/SGVector.h>
#include <Eigen/Eigen>

using namespace shogun;
using namespace std;
using namespace Eigen;

template <template <class,int...> class Vector,class T,int... Info>
struct type_traits;

template <> template <class T>
struct type_traits<SGVector, T>
{
	typedef typename SGVector<T>::value_type value_type;
};

template <> template <class T, int... Info>
struct type_traits<Matrix, T, Info...>
{
	typedef typename Matrix<T,Info...>::Scalar value_type;
};

template <template <class, int...> class Vector, class T, int... Info>
struct dot_impl
{
	static typename type_traits<Vector,T,Info...>::value_type compute(Vector<T,Info...> a, Vector<T,Info...> b);
};

template <> template <class T>
struct dot_impl<SGVector, T>
{
	static T compute(SGVector<T> a, SGVector<T> b)
	{
		typedef Matrix<T, Dynamic, 1> VectorXt;
		Map<VectorXt> av(a.vector, a.vlen);
		Map<VectorXt> bv(b.vector, b.vlen);
		return av.dot(bv);
	}
};

template <> template <class T, int... Info>
struct dot_impl<Matrix,T,Info...>
{
	static T compute(Matrix<T,Info...> a, Matrix<T,Info...> b)
	{
		return a.dot(b);
	}
};

namespace linalg
{

template <template <class,int...> class Vector, class T, int... Info>
typename type_traits<Vector,T,Info...>::value_type dot(Vector<T,Info...> a, Vector<T,Info...> b)
{
	return dot_impl<Vector,T,Info...>::compute(a, b);
}

}

int main()
{
	init_shogun_with_defaults();
	SGVector<float64_t> a(10);
	a.set_const(10);
	cout << linalg::dot(a, a) << endl;
	VectorXf b(10);
	b=VectorXf::Random(10);
	cout << linalg::dot(b, b) << endl;
	Vector3d c=Vector3d::Random();
	cout << linalg::dot(c, c) << endl;
	SGVector<int64_t> d(10);
	d.set_const(10);
	cout << linalg::dot(d, d) << endl;
	exit_shogun();
	return 0;
}