I am new to the HP-50g, and I am noticing the following problem.

If I have an expression, say,

M * Q * (Q+1) * (Q-1) + 1and I hit SIMPLIFY, then the 50g tries to find definitions for M and Q, not only in the current directory, but (at least) in all the path from the current directory to the root. So if, say, one level above while working on something else I have variable M with value 0.3, when I click SIMPLIFY the value will be plugged into the expression, and the result will not be an expression in M and Q any more.

--------------------------

M + M * Q

This is true also for EXPAND.

COLLECT works "correctly", just working on the equation at hand.

Is this the intended behavior?

How can I prevent variable expansion from taking place? I would simply like to be able to work on an expression, regardless of what variables I might have defined at an upper level (or at the same level).

I am using the latest ROM, C-2.15, if this makes a difference.

Many thanks!

Luca