public double calcObersumme()
	{
		double hoehe, erg;

		erg = 0.0;
		
		for(double i=intervalLeft; i<=intervalRight-dx+(dx/4); i+=dx)
		{
			int j1, j2;
			
			j1 = 0;
			
			
			while(points.get(j1).getX()<=i && j1 < points.size()-1)
			{
				j1++;
			}
			
			j2 = j1;
			
			while(points.get(j2).getX()<=i+dx && j2 < points.size()-1)
			{
				j2++;
			}
			
			hoehe = points.get(j1).getY();
			
			for(int j=j1; j<=j2; j++)
			{
				if(points.get(j).getY()>hoehe)
				{
					hoehe = points.get(j).getY();
				}
			}
			
			erg += dx*hoehe;			
		}
		
		return erg;
	}