Barry Kissane
Deleting programs
Programs remain in your calculator until you delete them. They are not affected by
turning the calculator off. To permanently delete a program, go to the program list
with , and press the continuation key. Use and to select the program name
from the list, and then press ( ). To delete all the programs in a calculator, choose
. ( ) instead of ( ).
In case you have pressed any keys by mistake, you then have a second chance to
confirm that you do actually want to erase the program. Press ( ) if you do and
any other key or ( ) if you don't.
Programs can also be deleted from the Memory mode, accessed by . In Memory
mode, you have a choice of finding out how much calculator memory is being used for
various things (Memory Usage) or of resetting the calculator (Reset).
There is also a ( ) key on the memory usage screen, which you can use to delete
all the programs at once, if you wish.
Resetting the calculator manually (with the emergency reset on the back of the
calculator) will also delete all the programs. See Appendix A of the User's Guide for
details and warnings about this.
If you press the Reset key in error (either in Memory mode or using the reset on the
back of the calculator), you still have one last chance to avoid deleting everything: Press
( ) instead of ( ).
And, finally …
Using programs like those in this book will allow you to do many powerful things with
your calculator.
However, the most powerful use of programming comes when you start to write
programs for yourself. The programs in this book are all fairly short, partly to make it
easier for you to see how they work. Once you have a good idea of how these
programs work, you may like to experiment with writing other programs for yourself.
Some aspects of mathematics are fairly routine, and so lend themselves to
programming. An example of this is the quadratic formula, used in program QuadEqtn.
Other examples are the formulae used in the Calendar and Heron programs. There are
many other formulas in mathematics for which programs can easily be written. These
include working out simple interest, compound interest, the area of a circle and the
cosine law.
Another aspect of mathematics for which programming is useful involves the use of
repetition. You might like to try writing programs to deal with sequences and series,
which are of this kind.
Many of the programs in this book make use of the random number generator to
simulate probabilities. You might like to try writing other programs that use this
calculator feature.
