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Types of operators

There are four different types of calculation operators: arithmetic, comparison, text concatenation, and reference.

The order in which Excel for the web performs operations in formulas

In some cases, the order in which a calculation is performed can affect the return value of the formula, so it's important to understand how the order is determined and how you can change the order to obtain the results you want.

The syntax of functions

The following example of the ROUND function rounding off a number in cell A10 illustrates the syntax of a function.

1. Structure. The structure of a function begins with an equal sign (=), followed by the function name, an opening parenthesis, the arguments for the function separated by commas, and a closing parenthesis.

2. Function name. For a list of available functions, click a cell and press SHIFT+F3.

3. Arguments. Arguments can be numbers, text, logical values such as TRUE or FALSE, arrays, error values such as #N/A, or cell references. The argument you designate must produce a valid value for that argument. Arguments can also be constants, formulas, or other functions.

4. Argument tooltip. A tooltip with the syntax and arguments appears as you type the function. For example, type =ROUND( and the tooltip appears. Tooltips appear only for built-in functions.

Entering functions

When you create a formula that contains a function, you can use the Insert Function dialog box to help you enter worksheet functions. As you enter a function into the formula, the Insert Function dialog box displays the name of the function, each of its arguments, a description of the function and each argument, the current result of the function, and the current result of the entire formula.

To make it easier to create and edit formulas and minimize typing and syntax errors, use Formula AutoComplete. After you type an = (equal sign) and beginning letters or a display trigger, Excel for the web displays, below the cell, a dynamic drop-down list of valid functions, arguments, and names that match the letters or trigger. You can then insert an item from the drop-down list into the formula.

Nesting functions

In certain cases, you may need to use a function as one of the arguments of another function. For example, the following formula uses a nested AVERAGE function and compares the result with the value 50.

1. The AVERAGE and SUM functions are nested within the IF function.

Valid returnsWhen a nested function is used as an argument, the nested function must return the same type of value that the argument uses. For example, if the argument returns a TRUE or FALSE value, the nested function must return a TRUE or FALSE value. If the function doesn't, Excel for the web displays a #VALUE! error value.

Nesting level limitsA formula can contain up to seven levels of nested functions. When one function (we'll call this Function B) is used as an argument in another function (we'll call this Function A), Function B acts as a second-level function. For example, the AVERAGE function and the SUM function are both second-level functions if they are used as arguments of the IF function. A function nested within the nested AVERAGE function is then a third-level function, and so on.

The A1 reference style

The default reference styleBy default, Excel for the web uses the A1 reference style, which refers to columns with letters (A through XFD, for a total of 16,384 columns) and refers to rows with numbers (1 through 1,048,576). These letters and numbers are called row and column headings. To refer to a cell, enter the column letter followed by the row number. For example, B2 refers to the cell at the intersection of column B and row 2.

Making a reference to another worksheetIn the following example, the AVERAGE worksheet function calculates the average value for the range B1:B10 on the worksheet named Marketing in the same workbook.

1. Refers to the worksheet named Marketing

2. Refers to the range of cells between B1 and B10, inclusively

3. Separates the worksheet reference from the cell range reference

The difference between absolute, relative and mixed references

Relative referencesA relative cell reference in a formula, such as A1, is based on the relative position of the cell that contains the formula and the cell the reference refers to. If the position of the cell that contains the formula changes, the reference is changed. If you copy or fill the formula across rows or down columns, the reference automatically adjusts. By default, new formulas use relative references. For example, if you copy or fill a relative reference in cell B2 to cell B3, it automatically adjusts from =A1 to =A2.

Absolute referencesAn absolute cell reference in a formula, such as $A$1, always refer to a cell in a specific location. If the position of the cell that contains the formula changes, the absolute reference remains the same. If you copy or fill the formula across rows or down columns, the absolute reference does not adjust. By default, new formulas use relative references, so you may need to switch them to absolute references. For example, if you copy or fill an absolute reference in cell B2 to cell B3, it stays the same in both cells: =$A$1.

Mixed referencesA mixed reference has either an absolute column and relative row, or absolute row and relative column. An absolute column reference takes the form $A1, $B1, and so on. An absolute row reference takes the form A$1, B$1, and so on. If the position of the cell that contains the formula changes, the relative reference is changed, and the absolute reference does not change. If you copy or fill the formula across rows or down columns, the relative reference automatically adjusts, and the absolute reference does not adjust. For example, if you copy or fill a mixed reference from cell A2 to B3, it adjusts from =A$1 to =B$1.

The 3-D reference style

Conveniently referencing multiple worksheetsIf you want to analyze data in the same cell or range of cells on multiple worksheets within a workbook, use a 3-D reference. A 3-D reference includes the cell or range reference, preceded by a range of worksheet names. Excel for the web uses any worksheets stored between the starting and ending names of the reference. For example, =SUM(Sheet2:Sheet13!B5) adds all the values contained in cell B5 on all the worksheets between and including Sheet 2 and Sheet 13.

• You can use 3-D references to refer to cells on other sheets, to define names, and to create formulas by using the following functions: SUM, AVERAGE, AVERAGEA, COUNT, COUNTA, MAX, MAXA, MIN, MINA, PRODUCT, STDEV.P, STDEV.S, STDEVA, STDEVPA, VAR.P, VAR.S, VARA, and VARPA.

• 3-D references cannot be used in array formulas.

• 3-D references cannot be used with the intersection operator (a single space) or in formulas that use implicit intersection.

What occurs when you move, copy, insert, or delete worksheetsThe following examples explain what happens when you move, copy, insert, or delete worksheets that are included in a 3-D reference. The examples use the formula =SUM(Sheet2:Sheet6!A2:A5) to add cells A2 through A5 on worksheets 2 through 6.

• Insert or copyIf you insert or copy sheets between Sheet2 and Sheet6 (the endpoints in this example), Excel for the web includes all values in cells A2 through A5 from the added sheets in the calculations.

• Delete If you delete sheets between Sheet2 and Sheet6, Excel for the web removes their values from the calculation.

• MoveIf you move sheets from between Sheet2 and Sheet6 to a location outside the referenced sheet range, Excel for the web removes their values from the calculation.

• Move an endpointIf you move Sheet2 or Sheet6 to another location in the same workbook, Excel for the web adjusts the calculation to accommodate the new range of sheets between them.

• Delete an endpointIf you delete Sheet2 or Sheet6, Excel for the web adjusts the calculation to accommodate the range of sheets between them.

The R1C1 reference style

You can also use a reference style where both the rows and the columns on the worksheet are numbered. The R1C1 reference style is useful for computing row and column positions in macros. In the R1C1 style, Excel for the web indicates the location of a cell with an "R" followed by a row number and a "C" followed by a column number.

When you record a macro, Excel for the web records some commands by using the R1C1 reference style. For example, if you record a command, such as clicking the AutoSum button to insert a formula that adds a range of cells, Excel for the web records the formula by using R1C1 style, not A1 style, references.

Types of names

There are several types of names that you can create and use.

Defined nameA name that represents a cell, range of cells, formula, or constant value. You can create your own defined name. Also, Excel for the web sometimes creates a defined name for you, such as when you set a print area.

Table nameA name for an Excel for the web table, which is a collection of data about a particular subject that is stored in records (rows) and fields (columns). Excel for the web creates a default Excel for the web table name of "Table1", "Table2", and so on, each time you insert an Excel for the web table, but you can change these names to make them more meaningful.

Creating and entering names

You create a name by using Create a name from selection. You can conveniently create names from existing row and column labels by using a selection of cells in the worksheet.

Note:By default, names use absolute cell references.

You can enter a name by:

• Typing Typing the name, for example, as an argument to a formula.

• Using Formula AutoCompleteUse the Formula AutoComplete drop-down list, where valid names are automatically listed for you.

Using array constants

In an ordinary formula, you can enter a reference to a cell containing a value, or the value itself, also called a constant. Similarly, in an array formula you can enter a reference to an array, or enter the array of values contained within the cells, also called an array constant. Array formulas accept constants in the same way that non-array formulas do, but you must enter the array constants in a certain format.

Array constants can contain numbers, text, logical values such as TRUE or FALSE, or error values such as #N/A. Different types of values can be in the same array constant— for example, {1,3,4;TRUE,FALSE,TRUE}. Numbers in array constants can be in integer, decimal, or scientific format. Text must be enclosed in double quotation marks — for example, "Tuesday".

Array constants cannot contain cell references, columns or rows of unequal length, formulas, or the special characters $ (dollar sign), parentheses, or % (percent sign).

When you format array constants, make sure you:

• Enclose them in braces ( { } ).

• Separate values in different columns by using commas (,). For example, to represent the values 10, 20, 30, and 40, you enter {10,20,30,40}. This array constant is known as a 1-by-4 array and is equivalent to a 1-row-by-4-column reference.

• Separate values in different rows by using semicolons (;). For example, to represent the values 10, 20, 30, and 40 in one row and 50, 60, 70, and 80 in the row immediately below, you enter a 2-by-4 array constant: {10,20,30,40;50,60,70,80}.