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Chapter 9 Formula Editor 311
Using Formula Editor Options
5 Click column B in the Table Columns list.
6 Click the addition button ( ) in the formula editor keypad.
7 Click column C in the Table Columns list.
9Formulas
Because the order of precedence determines which arguments are affected by each functions, it also
affects the grouping of expressions. Select functions in the formula to verify how the
order-of-precedence rules have been applied.
Structuring Formulas for Efficient Evaluation
Usually, it is not necessary to structure formulas with efficient evaluation in mind. Most formulas
evaluate almost instantaneously regardless of their structure. This is because statistical functions and
constant expressions are evaluated only once when a column’s values are calculated.
However, when you are creating conditional expressions, keep in mind that Match evaluates faster and
uses less memory than an equivalent Condition function, If. (Note that Match ignores trailing spaces,
while If does not.)
Consider two formulas for predicting a child’s height from his age shown in Figure 9.22. In each case
there is a base height of 58.125 inches to which a quantity is added depending on the value of the age
variable.
Figure 9.22 The Match Conditional Evaluates Faster Than the If Function
The Match conditional evaluates faster than the If function because the age variable is evaluated only
once for each row in the data table. The If condition must evaluate the age variable at each If clause for
each row until a clause evaluates as true.
Using Formula Editor Options
There are several options the formula editor makes available to you as you create formulas. The
following sections discuss each of these options.