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math.y1() function

content/flux/v0/stdlib/math/y1.md

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<!------------------------------------------------------------------------------ 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#L2267-L2267 Contributing to Flux: https://github.com/influxdata/flux#contributing Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md ------------------------------------------------------------------------------->

math.y1() returns the order-one Bessel function of the second kind.

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 order-one Bessel function of a value

js
import "math"

math.y1(x: 3.14)// 0.35853138083924085

Use math.y1 in map

js
import "math"
import "sampledata"

sampledata.float()
    |> map(fn: (r) => ({r with _value: math.y1(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
2021-01-01T00:00:00ZNaNt1
2021-01-01T00:00:10Z0.17792152059156155t1
2021-01-01T00:00:20Z-0.279177585983904t1
2021-01-01T00:00:30Z0.09355230538878848t1
2021-01-01T00:00:40Z0.06669358775929306t1
2021-01-01T00:00:50Z0.318734411734819t1
_time_value*tag
2021-01-01T00:00:00Z-0.17429072159140693t2
2021-01-01T00:00:10Z0.15797094698544048t2
2021-01-01T00:00:20ZNaNt2
2021-01-01T00:00:30Z-0.17740857181789169t2
2021-01-01T00:00:40Z-0.18452518993372807t2
2021-01-01T00:00:50Z-0.18788912184316153t2

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