STACK MECHANICS
The following assumes you are familiar with RPN else please turn to the HP-42S Owner’s Manual first.
The fate of particular stack register contents depends on the operation executed, its domain (real or complex) and the stack size cho-
sen. Real functions in a 4-level stack work as known for decades. In a larger stack, everything works alike on your WP 34S just with
more levels for intermediate results. Please note only the contents of X are displayed in any case. See below for details of the stack
mechanics:
Calculating formulas from inside out stays a wise strategy in either stack. With more levels, however, stack overflow will hardly ever
happen, even with the most advanced formulas you compute in your life as a scientist or engineer.