ContextQMD
Back to Influxdb

math.erf() function

content/flux/v0/stdlib/math/erf.md

latest3.0 KB
Original Source
<!------------------------------------------------------------------------------ IMPORTANT: This page was generated from comments in the Flux source code. Any edits made directly to this page will be overwritten the next time the documentation is generated. To make updates to this documentation, update the function comments above the function definition in the Flux source code: https://github.com/influxdata/flux/blob/master/stdlib/math/math.flux#L608-L608 Contributing to Flux: https://github.com/influxdata/flux#contributing Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md ------------------------------------------------------------------------------->

math.erf() returns the error function of x.

Function type signature
js
(x: float) => float

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

Parameters

x

({{< req >}}) Value to operate on.

Examples

Return the error function of a value.

js
import "math"

math.erf(x: 22.6)// 1.0

Use math.erf in map

js
import "math"
import "sampledata"

sampledata.float()
    |> map(fn: (r) => ({r with _value: math.erf(x: r._value)}))

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

Input data

_time*tag_value
2021-01-01T00:00:00Zt1-2.18
2021-01-01T00:00:10Zt110.92
2021-01-01T00:00:20Zt17.35
2021-01-01T00:00:30Zt117.53
2021-01-01T00:00:40Zt115.23
2021-01-01T00:00:50Zt14.43
_time*tag_value
2021-01-01T00:00:00Zt219.85
2021-01-01T00:00:10Zt24.97
2021-01-01T00:00:20Zt2-3.75
2021-01-01T00:00:30Zt219.77
2021-01-01T00:00:40Zt213.86
2021-01-01T00:00:50Zt21.86

Output data

_time_value*tag
2021-01-01T00:00:00Z-0.9979506490526588t1
2021-01-01T00:00:10Z1t1
2021-01-01T00:00:20Z1t1
2021-01-01T00:00:30Z1t1
2021-01-01T00:00:40Z1t1
2021-01-01T00:00:50Z0.9999999996270934t1
_time_value*tag
2021-01-01T00:00:00Z1t2
2021-01-01T00:00:10Z0.9999999999979144t2
2021-01-01T00:00:20Z-0.9999998862727434t2
2021-01-01T00:00:30Z1t2
2021-01-01T00:00:40Z1t2
2021-01-01T00:00:50Z0.9914724883356396t2

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