% Tracking Example 2: Snowplow
clear all;
x0=[5;0];

t0=0;
tf=10;
options=odeset('RelTol',1e-10,'AbsTol',1e-10');
figure(1); clf;
hold on;

[Ta,Xa]=ode45('snowplow', [t0 tf], x0,options);
plot(Xa(:,1),Xa(:,2),'.g');
grid

figure(2); clf;
hold on;
for i = 1:size(Ta)
  if ( Ta(i) < 10)
    w(i) = Ta(i)^2;
  else
    w(i) = 100 + 20*(Ta(i)-10);
  end
end
plot(Ta,w','.r'); 
plot(Ta,Xa(:,1),'.b');