aggregated(on:into:transform:)
Generates a data frame with a column for the group identifier and a column of values from the transform.
Declaration
func aggregated<Element, Result>(on columnID: ColumnID<Element>, into aggregatedColumnName: String? = nil, transform: (DiscontiguousColumnSlice<Element>) throws -> Result) rethrows -> DataFrameParameters
- columnID:
A column identifier.
- aggregatedColumnName:
The name of the aggregation column the method adds to the data frame.
- transform:
A closure that transforms each group’s elements in the column.