"Fitter" un cercle avec un nuage de points

double moyX = 0;
	for (int i = 0; i < points.size(); i++) {
		moyX += points[ i].x;
	}
	moyX /= points.size();
	double sommeA=0;
	for (int i = 0; i < points.size(); i++) {
		sommeA+=points[ i].y*points[ i].y;
	}
	double sommeB=0;
	for (int i = 0; i < points.size(); i++) {
		sommeB+=points[ i].y;
	}
	double sommeC=0;
	for (int i = 0; i < points.size(); i++) {
		sommeC+=points[ i].x*points[ i].x;
	}
	double sommeD=0;
	for (int i = 0; i < points.size(); i++) {
		sommeD+=points[ i].x;
	}
	double sommeE=0;
	for (int i = 0; i < points.size(); i++) {
		sommeE+=points[ i].x*points[ i].y;
	}
	double numerateur=0.5*(points.size()*sommeA-sommeB*sommeB-points.size()*sommeC+
	sommeD*sommeD);
	double denominateur=points.size()*sommeE-sommeB*sommeD;
	
	if (denominateur == 0)
	{
		this->vertical = true;
		this->x = moyX;
	}
	else
	{
		double c = numerateur / denominateur; 
		this->slope = c+sqrt(c*c+1);
		this->originOrdinate = (1/points.size())*(sommeB-(this->slope)*sommeD);
		this->vertical = false;
	}

Straight::Straight(vector<Point> points) {
	double moyX = 0;
	double moyY = 0;
	for (int i = 0; i < points.size(); i++) {
		moyX += points[ i].x;
		moyY += points[ i].y;
	}
	moyX /= points.size();
	moyY /= points.size();
	double sommeA=0;
	for (int i = 0; i < points.size(); i++) {
		sommeA+=(points[ i].x-moyX)*(points[ i].x-moyX);
	}
	double sommeB=0;
	for (int i = 0; i < points.size(); i++) {
		sommeB+=(points[ i].y-moyY)*(points[ i].y-moyY);
	}
	double sommeC=0;
	for (int i = 0; i < points.size(); i++) {
		sommeC+=(points[ i].x-moyX)*(points[ i].y-moyY);
	}
	double erreur = 0;
	cout << "sommeC = " << sommeC << endl;
	if (sommeC == 0)
	{
		cout << "vertical" << endl;
		this->vertical = true;
		this->x = moyX;
		for (int i = 0; i < points.size(); i++) {
			erreur += this->getDistance(points[ i]);
		}
	}
	else
	{
		double C=0.5*(sommeA-sommeB)/(2*sommeC);
		this->slope=-C+sqrt(C*C+1);
		this->originOrdinate=moyY-this->slope*moyX;
		double erreur1 = 0;
		for (int i = 0; i < points.size(); i++) {
			erreur1 += this->getDistance(points[ i]);
		}
		this->slope = -C - sqrt(C*C + 1);
		this->originOrdinate = moyY - this->slope*moyX;
		double erreur2 = 0;
		for (int i = 0; i < points.size(); i++) {
			erreur2 += this->getDistance(points[ i]);
		}
		if (erreur1 > erreur2) {
			erreur = erreur2;
			this->slope = -C - sqrt(C*C + 1);
		}
		else
		{
			erreur = erreur2;
			this->slope = -C+ sqrt(C*C + 1);
		}
		this->originOrdinate = moyY - this->slope*moyX;
		this->vertical = false;
	}
	
	this->error=erreur/points.size();
}