docs-v2/content/flux/v0/stdlib/universe/highestmax.md

title	description	menu	weight	flux/v0/tags	introduced
highestMax() function	`highestMax()` selects the record with the highest value in the specified `column` from each input table and returns the highest `n` records.	flux_v0_ref name parent identifier highestMax universe universe/highestMax	101	transformations selectors	0.7.0

highestMax() selects the record with the highest value in the specified column from each input table and returns the highest n records.

Note: highestMax() drops empty tables.

Function type signature

(<-tables: stream[A], n: int, ?column: string, ?groupColumns: [string]) => stream[A] where A: Record

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Parameters

n

({{< req >}}) Number of records to return.

column

Column to evaluate. Default is _value.

groupColumns

List of columns to group by. Default is [].

tables

Input data. Default is piped-forward data (<-).

Examples

Return the highest two values from a stream of tables

import "sampledata"

sampledata.int()
    |> highestMax(n: 2, groupColumns: ["tag"])

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Input data

_time	_value	*tag
2021-01-01T00:00:00Z	-2	t1
2021-01-01T00:00:10Z	10	t1
2021-01-01T00:00:20Z	7	t1
2021-01-01T00:00:30Z	17	t1
2021-01-01T00:00:40Z	15	t1
2021-01-01T00:00:50Z	4	t1

_time	_value	*tag
2021-01-01T00:00:00Z	19	t2
2021-01-01T00:00:10Z	4	t2
2021-01-01T00:00:20Z	-3	t2
2021-01-01T00:00:30Z	19	t2
2021-01-01T00:00:40Z	13	t2
2021-01-01T00:00:50Z	1	t2

Output data

_time	_value	tag
2021-01-01T00:00:00Z	19	t2
2021-01-01T00:00:30Z	17	t1

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