The style of calculation illustrated above, in which you enter numbers
onto the stack before you perform mathematical functions, is called
(Reverse Polish Notation),
postfix notation, or stack logic. Nearly
all HP-28S commands, not just calculations, use stack logic. This sys-
tem uses two simple rules:
• The inputs required by a function, called the
to the func-
tion, must be on the stack before the function is executed.
• The results of a function are returned to the stack, where they are
available as arguments to the next function.
You can also calculate by entering an expression in algebraic form, as
it might appear written in a book. In the next chapter you'll perform
the same calculation as above, using an algebraic expression.
An Overview of the Calculator
This section points out some major features of the calculator, includ-
ing a catalog of commands that lists and describes each command.
Major Features and Concepts
The illustrations on pages 26 and 27 show the calculator keyboard
and display, with important features identified. The numbers in the
following descriptions correspond to the numbers in the illustrations.
1: Getting Started