Enforcing state variable support (boundary constraints in ODE)

[Sohrab Salehi]

Hi, 

I have a vector X representing the states in the model.

They're frequencies and as such have to sum to one and lie between 0 and 1 (the simplex condition). 

I've implemented the transition using an ODE block in the Transition subroutine.

So far I'm enforcing the simplex condition via the conditional operator (?:).

I was wondering if there is more elegant solution to this?

Thank you!