Error using ode45

Dears,

I am having an error for ODE45 usage:

XDOT_P12_7B returns a vector of length 2, but the length of the initial conditions vector is 3. The vector returned by

XDOT_P12_7B and the initial conditions vector must have the same number of elements.

I don't see where the problem comes from, I define in the function file 3 variables and my derivative matrix also has 3 components only thing one of my derivatives is equal (it represents constant T)

I would be appreciated if someone can help me with this,

Thank you

Answer 1

[Bjorn Gustavsson]

Perhaps your calling has become too "traditional" and is not properly supported. In that case (and in general) it might be enough to change the calling of ode45 to:

[Vb,x]=ode45(@(V,x) xdot_P12_7b(V,x),Vspan,ic);

Answer 2

[Alan Stevens]

You need to declare cpAB as a global variable in P12_7b. Better to try to do without global variables!

You have some other problems also, but as I don't have fsolve I can't do much more.

[esra ilhan]

What are the other problems you see, I change the cpAB and updated ODE45 but still I have error