Array formulas allow you to perform laborious calculations on sets of data without having to do the intermediary stages in columns or rows of Excel. Using them makes the spreadsheet smaller and faster, but the formulas need to be checked carefully for mistakes.
For example, if you have a data set named "Data' in your spreadsheet, you could calculate the quantity:
\displaystyle\sum_{i=1}^{n}(x_{i}-\bar{x})^{3} | in one formula: |
{=SUM((Data-AVERAGE(Data))^3)}
The formula is placed into Excel by simply typing
=SUM((Data-AVERAGE(Data))^3)
and entering the formula using Ctrl+Shift+Enter to make it an array function, instead of the usual Enter. If you have a formula in an Excel cell that should be an array formula, but currently isn't, hit the F2 (Excel's edit) key, then press Ctrl+Shift+Enter. You can even link a Crystal Ball distribution to an array calculation.
