function [xt,vt] = cork1(pt,x0,v0)
%
%  The function [xt,vt] = cork1(pt,x0,v0) is similar to cork,
%  but the length of the cork is now 3.76 instead of 3.75.
%
%  ON ENTRY:
%    pt       proposed end time;
%    x0       initial position of the cork;
%    v0       initial velocity of the cork.
%
%  ON RETURN:
%    xt       location of the cork at pt;
%    vt       velocity of the cork at pt.
%
%  EXAMPLE:
%    [xt,vt] = cork(1.2457,0,0).
%
g = 9.81;    % five parameters: (g,q,D,gamma,R)
q = 20;
D = 5;
gamma = 1.4;
R = 4;
% The length of the cork is L:
L = 3.75;
% The 2nd order equation is written as a system of two
% first-order equations:
% f = inline('[x(2); g*(1+q)*((1+x(1)/D)^(-gamma) + R*t/100 - 1 + q*x(1)/(L*(1+q)))]', 't','x');
f = inline('[x(2); 9.81*(1+20)*((1+x(1)/5)^(-1.4) + 4*t/100 - 1 + 20*x(1)/(3.76*(1+20)))]', 't','x');
xzero = [x0 v0]; % initial conditions
tspan = [0 pt];
[t x] = ode45(f,tspan,xzero);
plot(t,x(:,1),'b');
xt = x(size(x,1),1)
vt = x(size(x,1),2)