functions

/*void rkd_tree::explore_best(std::shared_ptr<node> &current, const point &q, double &R, int &res, std::set<std::pair<double, int>> &pq, int m, int rp) {
	if(current == nullptr) return;
	if(current-> left == nullptr && current->right == nullptr && current->pts.size() != 0) {
		double d = dist(points[current->pts[0]], q);
		if(d < R) {
			R = d;
			res  = current->pts[0];
			double pmed = current->parent->median;
			int index = current->parent->index;
			point plane = q;
			plane[index] = pmed;
			double r = dist(plane, q);
			pq.insert({r, m});
		}

	} else {
		double med = current->median;
		int index  = current->index;
		point plane = q;
		plane[index] = med;
		double r = dist(plane, q);
		if(rp <= r) {
			if(q[index] <= med)
				explore_best(current->right, q, r, res, pq, m, rp);
			else
				explore_best(current->left, q, r, res, pq, m, rp);
		} else {
			if(q[index] <= med)
				explore_best(current->right, q, r, res, pq, m, rp);
			else
				explore_best(current->left, q, r, res, pq, m, rp);
		}
	}
}
*/


//	  double pmed  = current->parent->median;
//		int index    = current->parent->index;
//		point plane  = q;
//		plane[index] = pmed;
//		double r = dist(plane, q);
//		pq.insert({r, m});