core/org.jetbrains.kotlinx.dataframe.impl.aggregation.aggregators.multipleColumnsHandlers/NoMultipleColumnsHandler

NoMultipleColumnsHandler

internal class NoMultipleColumnsHandler<in Value : Any, out Return> : AggregatorMultipleColumnsHandler<Value, Return>

Constructors

constructor()

Properties

aggregator

open override var aggregator: Aggregator<Value, Return>?

Reference to the aggregator instance.

Functions

aggregateMultipleColumns

open override fun aggregateMultipleColumns(columns: Sequence<DataColumn<Value?>>): Return

Aggregates the data in the multiple given columns and computes a single resulting value. Calls Aggregator.aggregateSequence or Aggregator.aggregateSingleColumn.

calculateReturnTypeMultipleColumns

open override fun calculateReturnTypeMultipleColumns(colTypes: Set<KType>, colsEmpty: Boolean): KType

Function that can give the return type of aggregateMultipleColumns, given types of the columns. This allows aggregators to avoid runtime type calculations.

init

open fun init(aggregator: Aggregator<Value, Return>)