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

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title description menu weight flux/v0/tags introduced
lowestAverage() function `lowestAverage()` calculates the average of each input table and returns the lowest `n` averages.
flux_v0_ref
name parent identifier
lowestAverage universe universe/lowestAverage
101
transformations
selectors
0.7.0

lowestAverage() calculates the average of each input table and returns the lowest n averages.

Note: lowestAverage() drops empty tables.

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

{{% caption %}} For more information, see Function type signatures. {{% /caption %}}

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 lowest table average from a stream of tables

import "sampledata"

sampledata.int()
    |> lowestAverage(n: 1, 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

tag _value
t1 8.5

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