calling a c file to use ode45

I am trying to call a c file that hold a derivative function. I want to call it with ode45, or something similar.

[James Tursa]

Have you ever written a mex function before? What does the derivative function C signature look like?

Answer 1

[Steven Lord]

You can pass a function handle to a MEX-file that you've created from a C or C++ file into ode45 as long as the signature of that MEX-file matches the signature ode45 requires its ODE function (the first input) to have. See the description of the odefun input argument on the ode45 documentation page.

"The function dydt = odefun(t,y), for a scalar t and a column vector y, must return a column vector dydt of data type single or double that corresponds to f(t,y). odefun must accept both input arguments t and y, even if one of the arguments is not used in the function."