Month: February 2014

struct Point
{
	Point(int_t _x, int_t _y) : x(_x), y (_y)
	{

	}

	int_t x;
	int_t y;
};


typedef std::list points_t;

double euclideanDistance(const Point& lhs,const Point& rhs)
{
	 double p1 = std::pow((float)(rhs.x - lhs.x), 2);
	 double p2 =  std::pow((float)(rhs.y - lhs.y), 2);
	 double vd =  std::sqrt(p1 + p2);

	 return vd;
}


double hausdorffPHD(points_t seta, points_t setb)
{
    double maxDistance = 0;

    points_t::iterator afront = seta.begin();
    points_t::iterator aback  = seta.end();

    std::vector ranking;

    for(int_t i=0; afront != aback ; ++afront, ++i)
    {
    	Point* a = *afront;
        double minDistance = std::numeric_limits::max();

        points_t::iterator bfront = setb.begin();
        points_t::iterator bback  = setb.end();

    	for(; bfront != bback ; ++bfront)
	    {
    		Point* b = *bfront;
    		double ed = euclideanDistance(*a, *b);

            if (ed < minDistance)
                minDistance = ed;
	    }

    	ranking.push_back(minDistance);
    }

    std::sort(ranking.begin(), ranking.end());

    double fraction = .7;
    int k = (int) (seta.size() * fraction);
    return ranking[k];
}


double hausdorff(points_t seta, points_t setb)
{
    double habPHD = hausdorffPHD( seta, setb);
    double hbaPHD = hausdorffPHD( setb, seta);
    double distancePHD = std::max(habPHD, hbaPHD);
    printf("hd = %0.4f\t %0.4f\t %0.4f\t \n", distancePHD, habPHD, hbaPHD);
    return distancePHD;
}


int_t main(int_t argc, char_t** args)
{

	points_t seta;
	points_t setb;

	seta.push_back(new Point(1,2));
	seta.push_back(new Point(2, 4));

	setb.push_back(new Point(2, 4));
	setb.push_back(new Point(3, 4));

	double val = hausdorff(seta, setb);
}