This returns the result of each column 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 column as the first parameter. Used for aggregate functions or functions that apply on each column (such as a vertical 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.$$$(SUM)
gives row wise sums of each row.
Functions can be defined as a string with a variable, say, x. The following shows a calculation done in each column by subracting second from the first element in each column.
a.$$$("[x[2],x[0],x[2]-x[0]]")