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I'm trying to use MATLAB to obtain simulations for some equations that describe a model. I'm new to MATLAB (though I've taken a course in C++ and another in Java), so I read a bit on the mathworks website on solving ODEs, and settled on ode45

The equations I'm trying to model are the following (see link):

http://i.imgur.com/vWATx.jpg

As can be seen, the first equation is a straightforward (I guess?) ODE, where the L function is defined, for some x, as L(x)=coth(x)-(1/x). I was not sure how to write that (d ln L/dE)^(-1), so I just had WolframAlpha evaluate it and I typed it in.

Mentioned earlier, I believe that I got the code down for the first ODE:

Assuming this gives me the right value for E (I didn't know how to write xi_E on MATLAB), how do I go about to using the solution for E in the second equation? I thought defining the solution, i.e. something likePHP:

sol = ode45(@firstode,tspan,E0)

would do it...but that doesn't seem to work. Can y'all provide any suggestions?

NOTE: The code written does not include anything re. the second equation as I've yet to solve the dilemma I'm facing.

Sorry for the long post. Thanks all!

MATLAB's a bit strange -- this would be nicer on C++ :(

Sincerely,

RedAnsar

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# MATLAB - Using solution of one ODE in another

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