who can help me to solve the ODE functions ,please~~

please help me to solve the functions ,thanks a lot ~

Answer 1

[Star Strider]

OK. I just did.

[chris]

Could you tell how to make the matlab code to solve the problem? thanks a lot~

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[chris]

[Star Strider]

Those aren’t strictly ‘constraints’, they’re boundary values. You probably need to use bvp4c to solve your system. (That’s the one I’d start with, anyway.) It would be interesting to know what it applies to (obviously orbital mechanics), but what particular problem?

Start by defining your variables. (I used ‘q’ here, use anything you want.) The ODE functions all require that your ODE function return a column vector of derivatives. For example, your definitions could be:

r = q(1),  r’ = qdot(1)
v = q(2),  v’ = qdot(2)
ϴ = q(3),  ϴ’ = qdot(3)
w = q(4),  w’ = qdot(4)
m = q(5),  m’ = qdot(5)

Then start writing your ODE function code, and the other functions bvp4c needs. This will take some time, since BVPs are more involved than straightforward ODEs, and so is coding them. See the bvp4c documentation for details.

There’s a link at the end of the bvp4c documentation for the tutorial but I’ll mention it here as well: Tutorial on solving BVPs with BVP4C.