% runpottopf  Kugelbewegung im parabolischen
%     Potentialtopf
yini = [2 -3 0 2]'
[ts,ys] = ode45('pottopfbahn',94, yini);
rar = sqrt(ys(:,1).^2 + ys(:,3).^2);
zar = 0.2*rar.^2;
plot(ts,ys) ;pause
plot(ys(:,1),ys(:,3)); axis equal ; pause
plot(ts,rar); pause
plot3(ys(:,1),ys(:,3),zar); axis equal; box on
