To calculate a single result This type of array formula can simplify a worksheet model by replacing several different formulas with a single array formula.
For example, the following calculates the total value of an array of stock prices and shares, without using a row of cells to calculate and display the individual values for each stock.
Array formula that produces a single result
When you enter the formula ={SUM(B2:D2*B3:D3)} as an array formula, it multiples the Shares and Price for each stock, and then adds the results of those calculations together.
To calculate multiple results Some worksheet functions return arrays of values, or require an array of values as an argument. To calculate multiple results with an array formula, you must enter the array into a range of cells that has the same number of rows and columns as the array arguments.
For example, given a series of three sales figures (in column B) for a series of three months (in column A), the TREND function determines the straight-line values for the sales figures. To display all of the results of the formula, it is entered into three cells in column C (C1:C3).
Array formula that produces multiple results
When you enter the formula =TREND(B1:B3,A1:A3) as an array formula, it produces three separate results (22196, 17079, and 11962), based on the three sales figures and the three months.
Using array constantsIn 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 nonarray 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
Array constants cannot contain cell references, columns or rows of unequal length, formulas, or the special characters $ (dollar sign), parentheses, or % (percent sign).
The format of array constants
Array constants are enclosed in braces ( { } ).
Separate values in different columns with commas (,). For example, to represent the values 10, 20, 30, and 40, 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 with 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 would enter a 2-by-4 array constant: {10,20,30,40;50,60,70,80}.