MATLAB: The example from internet doesn’t work in matlab (ODE45 for solving equation system)

dynamics solutionode45system of equationunexpected matlab expression

Im new on matlab, and ill trying learn how to solve some equation systems using matlab, and ode45 solver. I was tried to use a sample from matlab help, and it works great, but when im trying to solve a little bit difficult equations i get the error. its happen with all my tried was the same ( i have a six motion equation system with 6 variables, so i need to leart how to solve it using matlab) I find some example on internet and try to solve and test it on my computer, but it doesn't work, i get some error:
          >> [T, XY] ode45('diffxy',0,10,[0 1 0])
       [T, XY] ode45('diffxy',0,10,[0 1 0])
               |
      Error: Unexpected MATLAB expression.
Can someone help for me?
Source of full code and description ill find on: http://www.mit.edu/people/abbe/matlab/ode.html
What is wrong here, what i need to change for the correct result, and what is the mistake explanation?
the *.m code:
function dxy = diffxy(t, xy)
%





%split xy into variables in our equations
%
x = xy(1);
xdot = xy(2);
y = xy(3);
%
% define the derivatives of these variables from equations
%
xdot = xdot;
ydot = 3*x + 2*y + 5;
xdoubledot = 3 - ydot + 2*xdot;
%
%return the derivatives in dxy in the right order
%
dxy = [xdot; xdoubledot; ydot]

Best Answer

When you called it you left out an equals sign, to start.
[T, XY] ode45('diffxy',0,10,[0 1 0]) %from this
[T, XY] = ode45('diffxy',0,10,[0 1 0]) %to this
The unrecognized expression error occurs right at the first character after where the equal sign should have been.
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