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title description aliases menu weight flux/v0.x/tags related introduced
derivative() function The `derivative()` function computes the rate of change per unit of time between subsequent non-null records.
/influxdb/v2.0/reference/flux/functions/transformations/aggregates/derivative
/influxdb/v2.0/reference/flux/functions/built-in/transformations/aggregates/derivative/
/influxdb/v2.0/reference/flux/stdlib/built-in/transformations/derivative/
/influxdb/cloud/reference/flux/stdlib/built-in/transformations/derivative/
flux_0_x_ref
name parent
derivative universe
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transformations
/{{< latest "influxdb" >}}/query-data/flux/rate/
/{{< latest "influxdb" "v1" >}}/query_language/functions/#derivative, InfluxQL – DERIVATIVE()
0.7.0

The derivative() function computes the rate of change per unit of time between subsequent non-null records. It assumes rows are ordered by the _time column. The output table schema is the same as the input table.

Output data type: Float

derivative(
    unit: 1s,
    nonNegative: false,
    columns: ["_value"],
    timeColumn: "_time",
)

Parameters

unit

The time duration used when creating the derivative. Default is 1s.

nonNegative

Indicates if the derivative is allowed to be negative. Default is false. When true, if a value is less than the previous value, it is assumed the previous value should have been a zero.

columns

The columns to use to compute the derivative. Default is ["_value"].

timeColumn

The column containing time values. Default is "_time".

tables

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

Output tables

For each input table with n rows, derivative() outputs a table with n - 1 rows.

Examples

{{% flux/sample-example-intro plural=true %}}

Calculate the rate of change per second

import "sampledata"

sampledata.int()
    |> derivative()

{{< expand-wrapper >}} {{% expand "View input and output" %}} {{< flex >}} {{% flex-content %}}

Input data

{{% flux/sample set="int" %}}

{{% /flex-content %}} {{% flex-content %}}

Output data
_time tag _value
2021-01-01T00:00:10Z t1 1.2
2021-01-01T00:00:20Z t1 -0.3
2021-01-01T00:00:30Z t1 1
2021-01-01T00:00:40Z t1 -0.2
2021-01-01T00:00:50Z t1 -1.1
_time tag _value
2021-01-01T00:00:10Z t2 -1.5
2021-01-01T00:00:20Z t2 -0.7
2021-01-01T00:00:30Z t2 2.2
2021-01-01T00:00:40Z t2 -0.6
2021-01-01T00:00:50Z t2 -1.2

{{% /flex-content %}} {{< /flex >}} {{% /expand %}} {{< /expand-wrapper >}}

Calculate the non-negative rate of change per second

import "sampledata"

sampledata.int()
    |> derivative(nonNegative: true)

{{< expand-wrapper >}} {{% expand "View input and output" %}} {{< flex >}} {{% flex-content %}}

Input data

{{% flux/sample set="int" %}}

{{% /flex-content %}} {{% flex-content %}}

Output data
_time tag _value
2021-01-01T00:00:10Z t1 1.2
2021-01-01T00:00:20Z t1
2021-01-01T00:00:30Z t1 1
2021-01-01T00:00:40Z t1
2021-01-01T00:00:50Z t1
_time tag _value
2021-01-01T00:00:10Z t2
2021-01-01T00:00:20Z t2
2021-01-01T00:00:30Z t2 2.2
2021-01-01T00:00:40Z t2
2021-01-01T00:00:50Z t2

{{% /flex-content %}} {{< /flex >}} {{% /expand %}} {{< /expand-wrapper >}}

Calculate the rate of change per second with null values

import "sampledata"

sampledata.int(includeNull: true)
    |> derivative()

{{% expand "View input and output" %}} {{< flex >}} {{% flex-content %}}

Input data

{{% flux/sample "int" true %}}

{{% /flex-content %}} {{% flex-content %}}

Output data
_time tag _value
2021-01-01T00:00:10Z t1
2021-01-01T00:00:20Z t1 0.45
2021-01-01T00:00:30Z t1
2021-01-01T00:00:40Z t1
2021-01-01T00:00:50Z t1 -0.1
_time tag _value
2021-01-01T00:00:10Z t2
2021-01-01T00:00:20Z t2 -0.7
2021-01-01T00:00:30Z t2 2.2
2021-01-01T00:00:40Z t2
2021-01-01T00:00:50Z t2 -0.9

{{% /flex-content %}} {{< /flex >}} {{% /expand %}}