74 Section 5: Additional Operating Features
If a calculation results in a number whose magnitude is less than 10-
99
, the
calculation is not halted, but the value 0 is used for that number in subsequent
calculations.
Errors. If you attempt an improper operation – such as division by zero – the
calculator will display the word Error followed by a digit (0 through 9). To clear
the Error display, press any key. This does not execute that key’s function, but
does restore the calculator to its condition before the improper operation was
attempted. Refer to Appendix D for a list of error conditions.
Pr Error. If power to the calculator is interrupted, the calculator will display Pr
Error when next turned on. This indicates that Continuous Memory – which
contains all data, program, and status information – has been reset.
The ~ Key
Suppose you need to subtract $25.83 from $144.25, and you (mistakenly) key in
25.83, press \, then key in 144.25. But then you realize that when written
down on paper, the desired calculation reads 144.25 – 25.83, so that you have
unfortunately keyed in the second number first. To correct this mistake, merely
exchange the first and second numbers by pressing ~, the exchange key.
The ~ key is also useful for checking the first number entered to make sure
you keyed it in correctly. Before pressing the operation key, however, you should
press ~ again to return the second number entered to the display. Regardless
of how many times you press ~, the calculator considers the number in the
display to be the second number entered.
The F Key
Occasionally you may want to recall to the display the number that was there
before an operation was performed. (This is useful for doing arithmetic
calculations with constants and for recovering from errors in keying in numbers.)
To do so, press gF (last x).
Keystrokes (RPN mode) Display
25.83\144.25
144.25
Oops! You mistakenly keyed in the
second number first.
~
25.83
Exchanges the first and second
numbers. The first number keyed in
is now in the display.
-
118.42
The answer is obtained by pressing
the operation key.
