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% Compute trajectory of double pendulum
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tspan		= [0:0.01:10];			% time boundaries, note the syntax for explicit time step
theta10			= pi/2;			% initial angle theta1
theta1_dot0		= 0;			% initial velocity theta1_dot
theta20			= pi/2;			% initial angle theta2
theta2_dot0		= 0;			% initial velocity theta2_dot

%initial state 
x0		= [theta10;theta1_dot0;theta20;theta2_dot0];

%the only real parameter in those equations is 'g/l', that we
%declare as a global veriable:
global g_L 
g_L=10;

%Call to the matlab solver: 
[t,x]	= ode45('f',tspan, x0);

%Feel free to plot your results, or compare to the ones given in
%the testcase