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math.ilogb() function

content/flux/v0/stdlib/math/ilogb.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#L1072-L1072 Contributing to Flux: https://github.com/influxdata/flux#contributing Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md ------------------------------------------------------------------------------->

math.ilogb() returns the binary exponent of x as an integer.

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

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

Parameters

x

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

Examples

Return the binary exponent of a value

js
import "math"

math.ilogb(x: 123.45)// 6

Use math.ilogb in map

js
import "sampledata"
import "math"

sampledata.float()
    |> map(fn: (r) => ({r with _value: math.ilogb(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
2021-01-01T00:00:00Z1t1
2021-01-01T00:00:10Z3t1
2021-01-01T00:00:20Z2t1
2021-01-01T00:00:30Z4t1
2021-01-01T00:00:40Z3t1
2021-01-01T00:00:50Z2t1
_time_value*tag
2021-01-01T00:00:00Z4t2
2021-01-01T00:00:10Z2t2
2021-01-01T00:00:20Z1t2
2021-01-01T00:00:30Z4t2
2021-01-01T00:00:40Z3t2
2021-01-01T00:00:50Z0t2

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