AggCount

AggCount returns an aggregator that computes the number of elements within an aggregation group.

Syntax

AggCount(resultColumn)

Parameters

Parameter	Type	Description
resultColumn	String	The name of the output column that will contain the number of elements in each group.

Returns

An aggregator that computes the number of elements within an aggregation group, for each group.

Examples

In this example, AggCount adds a count column, Number, while AggAvg returns the average Number, as grouped by X.

import static io.deephaven.api.agg.Aggregation.AggCount
import static io.deephaven.api.agg.Aggregation.AggAvg

source = newTable(
    stringCol("X", "A", "B", "A", "C", "B", "A", "B", "B", "C"),
    stringCol("Y", "M", "P", "O", "N", "P", "M", "O", "P", "N"),
    intCol("Number", 55, 76, 20, 130, 230, 50, 73, 137, 214),
)

result = source.aggBy([AggCount("Number"),AggAvg("AvgNumber = Number")], "X")

source

result

Related documentation

• Create a new table
• How to create multiple summary statistics for groups
• aggBy
• Javadoc
• Pydoc