%                      BASEBALL.M
%
%
%
 
  clear
 
%
% Input physical variable, work variables and initial conditions.
%

  c_D = 0.4;
  rho = 0.0023;
  g = 32.2;
  m = .319/g;
  R = .121;
  A = pi*(R^2);
  k_D = c_D*rho*A/(2*m);

  k_L = R*rho*A/(2*m);

 
  T_f = 0.6;
  tspan = 0:T_f/100:T_f;

  omega = [0 0 0];
  u0 = [0 125 0 0 4 5];
 
%
%  Now let's integrate the system over the time inverval [0,Tf]
%  using the Runge-Kutta routine ode45.m.   
% 

  options = odeset('RelTol',1e-4,'AbsTol',1e-4);
  [T,Uapp] = ode45('baseball_eval',tspan,u0,options,k_D,k_L,g,omega);

%
%  Finally, we'll plot the solution.  Remember that Uapp has
%  the following components:  
% 
%    Uapp = [x v_x y v_y z v_z]
%

  x   = Uapp(:,1);
  v_x = Uapp(:,2);
  y   = Uapp(:,3);
  v_y = Uapp(:,4);
  z   = Uapp(:,5);
  v_z = Uapp(:,6);

  figure(1)
  plot(x(1:86),z(1:86))
  axis([0 60 0 7])
  xlabel('x-axis')
  ylabel('z-axis')

%
% End of program
%