If so how, and what value would this rating have in understanding the code?For example, I would guess that programs using genetic or neutral algorithms would be less predictable than one calculating the sum of pi.
Is it possible to rate how predictable a program's behavior will be?
software evaluation
You seem to be asking a variation of the halting problem, so no, there is not a general solution to determine how predictable a program is.However, you can throw a battery of tests and code reviews at any application and get a heuristic confidence to a program's predictability.