You can define two m files to run the simulation of
the differential equations. One m file defines the
equations, the other does the simulation.

To simulate a system of two variables with differential
equations:

	x1' = (1 - 0.01*x2)*x1
	x2' = (-1 + 0.02*x1)*x2

We write one m file that defines the equations:
(which must be called inel.m in this example)

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function xp = inel(t,x);

% Solves differential equations
% March 5, 1998

xp(1) = (1 - .01*x(2))*x(1);
xp(2) = (-1 + .02*x(1))*x(2);

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and another m file that runs the simulation:

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% Define the starting and ending times, and the
% initial conditions.

t0=0;
tfinal=10;
x0=[10 0]';

[t,x]=ode45('inel',t0,tfinal,x0);

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