Casio ALGEBRA FX 2.0, User Manual

Page: 316 / 426

19990401
8-3-1
Editing Program Contents
8-3 Editing Program Contents
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Debugging a Program
A problem in a program that keeps the program from running correctly is called a “bug,” and
the process of eliminating such problems is called “debugging.” Either of the following
symptoms indicates that your program contains bugs that require debugging.
• Error messages appearing when the program is run
• Results that are not within your expectations
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To eliminate bugs that cause error messages
An error message, like the one shown below, appears whenever something illegal occurs
during program execution.
When such a message appears, press
i
to display the place in the program where the error
was caused. The cursor will be flashing at the location of the problem. Check the “Error
Message Table” (page
$
-1-1) for steps you should take to correct the situation.
• Note that pressing
i
does not display the location of the error if the program is
password protected. Instead, it returns to the program list screen.
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To eliminate bugs that cause bad results
If your program produces results that are not what you normally expect, check the
contents of the program and make necessary changes.
The
1
(JUMP) key is also useful when editing program contents.
1
(JUMP)
b
(Top) ....... Moves the cursor to the
top of the program
1
(JUMP)
c
(Bottom)…Moves the cursor to the
bottom of the program