Array.$$()
Array.$$(Function|Array of Functions[,param1,param2,...])
This returns the result of each row of the Array being operated on by the function or array of functions passed. The parameters provided following the function/function array is passed to the function with each row as the first parameter. Used for aggregate functions or functions that apply on each row (such as a spreadsheet calculation).
For example, a=|4,4,1..10|
| 1 | 2 | 3 | 4 |
| 5 | 6 | 7 | 8 |
| 9 | 10 | 1 | 2 |
| 3 | 4 | 5 | 6 |
a.$$(SUM)
| 10 |
| 26 |
| 22 |
| 18 |
gives row wise sums of each row.