Parameters, Value
The standard deviation function calculates the standard deviation value of a column of data. It only keeps the data column as well as its homologous columns after aggregation, and it abandons other columns.
Syntax:
- Format: stddev(
<column>) - Parameters: see table below
- Value: ATTR ( number )
| Name | Category | Specification | Description |
|---|---|---|---|
<column> |
NODE，EDGE，PATH，ATTR，ARRAY，TABLE | / | the column to be aggregated |
The value of <column> with different categories in every row:
| Type | Value |
|---|---|
| NODE | Node's UUID in the row |
| EDGE | Edge's UUID in the row |
| PATH | ROW INDEX（starts from 0）in the row |
| ATTR | ATTR's value in the row |
| ARRAY | The value of the 1st element in the array of the row |
| TABLE | ROW INDEX（starts from 0）in the row |
ATTR (Numeric value)
Example: find the outbound 1-step paths from Card CA001, and calculate the standard deviation value of the amount of money transferred
n({_id == "CA001"}).re({@transfer} as pay).n({@card})
return stddev(pay.amount)