HP HP-20S - Page 64

545
2NN
But what if you wanted to find the area of many different pipes?
Rather than repeat the keystrokes each time (varying only the “5” for
the different diameters), you can put the repeatable keystrokes into a
program that would look like this:
01 x?2
02 X
03
04
05 4
06 =
This program assumes that the value for the diameter is in the display
when the program starts to run. It calculates and displays the area. To
enter this program into program memory, press the following keys.
(Don’t worry about the numbers that appear in your display—they’re
called keycodes and are explained later.) If you notice a mistake while
typing a line, press (4] to erase the line, then type it over.
62 6: Programming