Page 230 - Excel 2007 Bible

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Introducing Formulas and Functions
Editing Formulas
After you’ve entered a formula, you can (of course) edit that formula. You may need to edit a formula if you
make some changes to your worksheet and then have to adjust the formula to accommodate the changes.
Or the formula may return an error value, in which case you edit the formula to correct the error.
The following are some of the ways to get into cell edit mode:
n Double-click the cell, which enables you to edit the cell contents directly in the cell.
n Press F2, which enables you to edit the cell contents directly in the cell.
n Select the cell that you want to edit, and then click in the Formula bar. This enables you to edit
the cell contents in the Formula bar.
n If the cell contains a formula that returns an error, Excel will display a small triangle in the upper-
left corner of the cell. Activate the cell, and you’ll see a Smart Tag. Click the Smart Tag, and you
can choose one of the options for correcting the error. (The options will vary according to the
type of error in the cell.)
You can control whether Excel displays these formula-error-checking Smart Tags in the
TIP
TIP
Formulas section of the Excel Options dialog box. To display this dialog box, select Office ➪
Excel Options. If you remove the check mark from Enable Background Error Checking, Excel no longer dis- 11
plays these Smart Tags.
While you’re editing a formula, you can select multiple characters either by dragging the mouse cursor over
them or by pressing Shift while you use the direction keys.
TIP If you have a formula that you can’t seem to edit correctly, you can convert the formula to text
TIP
and tackle it again later. To convert a formula to text, just remove the initial equal sign (=).
When you’re ready to try again, type the initial equal sign to convert the cell contents back to a formula.
Using Cell References in Formulas
Most formulas you create include references to cells or ranges. These references enable your formulas to
work dynamically with the data contained in those cells or ranges rather than being restricted to fixed val-
ues. For example, if your formula refers to cell A1 and you change the value contained in A1, the formula
result changes to reflect the new value. If you didn’t use references in your formulas, you would need to edit
the formulas themselves in order to change the values used in the formulas.
Using relative, absolute, and mixed references
When you use a cell (or range) reference in a formula, you can use three types of references:
n Relative: The row and column references can change when you copy the formula to another cell
because the references are actually offsets from the current row and column.
n Absolute: The row and column references do not change when you copy the formula because the
reference is to an actual cell address.
n Mixed: Either the row or column reference is relative, and the other is absolute.

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