Glad to see that my solution in the other thread worked for you. You might want to post that it worked in that thread, so people who find your thread through google know the solution worked. This forum exists for the benefit of everyone.

You're very close actually. You're not declaring the variables wrong, just using them in the wrong way.

If you want to use variables from a base class, even if you have access to them, you must still explicitly say they're in the base class. Like

Code:

Gsum = Sum<T>::x + Sum<T>::y + Sum<T>::z + Gx + Gy + Gz;

When I do this for all the Sum variables you access in GrandSum, your code works fine.