Page 318 - Excel 2013 All-in-One For Dummies

300 Formulas 101 Formulas 101
From the simple addition formula to the most complex ANOVA statistical variation, all formulas in Excel have one thing in common: They all begin with the equal sign (=). This doesn’t mean that you always have to type in the equal sign — although if you do, Excel expects that a formula of some type is to follow. When building a formula that uses a built-in function, often- times you use the Insert Function button on the Formula bar to select and insert the function, in which case, Excel adds the opening equal sign for you.
If you’re an old Lotus 1-2-3 user and you type @@ to start a function, Excel automatically converts the @@ sign into the equal sign the moment that you complete the formula entry. It does mean, however, that each and every completed formula that appears on the Formula bar starts with the equal sign.
When building your formulas, you can use constants that actually contain the number that you want used in the calculation (such as “4.5%,” “$25.00,” or “–78.35”), or you can use cell addresses between the operators or as the arguments of functions. When you create a formula that uses cell addresses, Excel then uses the values that you’ve input in those cells in calculating
the formula. Unlike when using constants in formulas, when you use cell addresses, Excel automatically updates the results calculated by a formula whenever you edit the values in the cells to which it refers.
Formula building methods
When building formulas manually, you can either type in the cell addresses or you can point to them in the worksheet. Using the Pointing method to supply the cell addresses for formulas is often easier and is always a much more foolproof method of formula building; when you type in a cell address, you are less apt to notice that you’ve just designated the wrong cell than when pointing directly to it. For this reason, stick to pointing when build- ing original formulas and restrict typing cell addresses to the odd occasion when you need to edit a cell address in a formula and pointing to it is either not practical or just too much trouble.
When you use the Pointing method to build a simple formula that defines a sequence of operations, you stop and click the cell or drag through the cell range after typing each operator in the formula. When using the method
to build a formula that uses a built-in function, you click the cell or drag through the cell range that you want used when defining the function’s argu- ments in the Function Arguments dialog box.