Microsoft Office

Part IV
Using Advanced Excel Features
n
n
Circular references: A circular reference occurs when a formula refers to its own cell, either
directly or indirectly. Circular references are useful in a few cases, but most of the time a circular
reference indicates a problem.
Array formula entry error: When entering (or editing) an Array formula, you must use
Ctrl+Shift+Enter to enter the formula. If you fail to do so, Excel doesn’t recognize the formula as
an Array formula, and you may get an error or incorrect results.
n Incomplete calculation errors: The formulas simply aren’t calculated fully. Microsoft has
acknowledged some problems with Excel’s calculation engine in some versions of Excel. To ensure
that your formulas are fully calculated, use Ctrl+Alt+F9.
Syntax errors are usually the easiest to identify and correct. In most cases, you’ll know when your formula
contains a syntax error. For example, Excel won’t permit you to enter a formula with mismatched parentheses.
Other syntax errors also usually result in an error display in the cell.
The following sections describe common formula problems and offers advice on identifying and correcting
them.
Mismatched parentheses
In a formula, every left parenthesis must have a corresponding right parenthesis. If your formula has mismatched
parentheses, Excel usually won’t permit you to enter it. An exception to this rule involves a simple
formula that uses a function. For example, if you enter the following formula (which is missing a closing
parenthesis), Excel accepts the formula and provides the missing parenthesis.
=SUM(A1:A500
A formula may have an equal number of left and right parentheses, but the parentheses may not match
properly. For example, consider the following formula, which converts a text string such that the first character
is uppercase and the remaining characters are lowercase. This formula has five pairs of parentheses,
and they match properly.
=UPPER(LEFT(A1))&RIGHT(LOWER(A1),LEN(A1)-1)
The following formula also has five pairs of parentheses, but they are mismatched. The result displays a syntactically
correct formula that simply returns the wrong result.
=UPPER(LEFT(A1)&RIGHT(LOWER(A1),LEN(A1)-1))
Often, parentheses that are in the wrong location will result in a syntax error — which is usually a message
that tells you that you entered too many or too few arguments for a function.
TIP
Excel can help you out with mismatched parentheses. When you’re editing a formula and you
move the cursor over a parenthesis, Excel displays it (and its matching parenthesis) in bold for
about one-half second. In addition, Excel color codes nested parentheses while you are editing a formula.
Cells are filled with hash marks
A cell is filled with a series of hash marks (#) for one of two reasons:
n
n
The column is not wide enough to accommodate the formatted numeric value. To correct it, you
can make the column wider or use a different number format.
The cell contains a formula that returns an invalid date or time. For example, Excel doesn’t support
dates prior to 1900 or the use of negative time values. Attempting to display either of these
values results in a cell filled with hash marks. Widening the column won’t fix it.
552