114 Section 8: Programming BasicsSetting the Calculator to a Particular Program Line

There will be occasions when you’ll want to set the calculator directly to a particular program line — such as when you’re storing a second program in program memory or when you’re modifying an existing program. Although you can set the calculator to any line by using Ças described above, you can do so more quickly as follows:

zWith the calculator in Program mode, pressing gi.followed by three digit keys sets the calculator to the program line specified by the digit keys, and then displays that line number and the keycode of the instruction stored there.

zWith the calculator in Run mode, pressing gi followed by three digit keys sets the calculator to the program line specified by the digit keys. Since the calculator is not in Program mode, the line number and keycode are not displayed.

The decimal point is not necessary if the calculator is in Run mode, but it is necessary if the calculator is in Program mode.

For example, assuming the calculator is still in Program mode, you can set it to program line 000 as follows:

KeystrokesDisplay

gi.000

000,

Program line 000

Executing a Program One Line at a Time

Pressing Çrepeatedly with the calculator in Program mode (as described earlier) enables you to verify that the program you have stored is identical to the program you wrote — that is, to verify that you have keyed the instructions in correctly. However, this does not ensure that the program you wrote calculates the desired results correctly: even programs created by the most experienced programmers often do not work correctly when they are first written.

To help you verify that your program works correctly, you can execute the program one line at a time, using the Ç key. Pressing Ç while the calculator is in Run mode advances the calculator to the next line in program memory, then displays that line’s number and the keycode of the instruction stored there, just as in Program mode. In Run mode, however, when the Ç key is released the instruction in the program line just displayed is executed and the display then shows the result of executing that line.

For example, to execute the program stored in the calculator one line at a time:

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