function main
% a simple example to solve ODE's
% Uses ODE45 to solve
%    dx_dt(1) = -1*x(1)-1*x(2)
%    dx_dt(2) = 1*x(1) -2*x(2)
%set an error
options=odeset('RelTol',1e-6,'Stats','on');
%initial conditions
Xo = [1;1];
%timespan
tspan = [0,5];
%call the solver
tic
[t,X] = ode45(@TestFunction,tspan,Xo,options);
toc
%plot the results
figure
hold on
plot(t,X(:,1));plot(t,X(:,2),':')
legend('x1','x2');ylabel('x');xlabel('t')
return
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function [dx_dt]= TestFunction(t,x)
%a function which returns a rate of change vector
M = [-1,-1;...
      1,-2]
dx_dt = M*x;
return
M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2


M =

    -1    -1
     1    -2

25 successful steps
0 failed attempts
151 function evaluations
Elapsed time is 0.723329 seconds.