Solving Coupled ODE's with Runge Kutta.

I want to solve a second order ODE of the form y''=Ey. To do this I've written my own Runge-Kutta function, which applies the 4th order Runge Kutta method to a function'f', defined using a function handle. To do this I have separated the ODE to a coupled first order system: y'=v, v'=Ey. However, I can't think of a way to input this coupled system with function handles. Is there a way to do this?

Answer 1

[James Tursa]

Do it the same way the examples for ode45 do it in the doc. Let your state vector be two elements with

y(1) = your original y
y(2) = your original v

Then you can have a function handle as follows:

dy = @(y) [y(2);E*y(1)];