double low=-2*Math.PI;
double high=2*Math.PI;

int []xPoints = new int[size.width];
        int []yPoints = new int[size.width];
        for(int i=0;i<size.width;i++){
            xPoints[i] = i;
            yPoints[i] = size.height/2 -(int)(size.height/3*Math.sin(low+i*(high-low)/size.width));
        }
        g.drawPolyline(xPoints, yPoints, size.width);
    }