docs-v2/content/flux/v0/stdlib/math/frexp.md

title	description	menu	weight
math.frexp() function	`math.frexp()` breaks `f` into a normalized fraction and an integral part of two.	flux_v0_ref name parent identifier math.frexp math math/frexp	101

math.frexp() breaks f into a normalized fraction and an integral part of two.

It returns frac and exp satisfying f == frac x 2**exp, with the absolute value of frac in the interval [1/2, 1).

Function type signature

(f: float) => {frac: float, exp: int}

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

Parameters

f

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

Examples

• Return the normalize fraction and integral of a value
• Use math.frexp in map

Return the normalize fraction and integral of a value

import "math"

math.frexp(f: 22.0)// {exp: 5, frac: 0.6875}

Use math.frexp in map

import "sampledata"
import "math"

sampledata.float()
    |> map(
        fn: (r) => {
            result = math.frexp(f: r._value)

            return {r with exp: result.exp, frac: result.frac}
        },
    )

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Input data

_time	*tag	_value
2021-01-01T00:00:00Z	t1	-2.18
2021-01-01T00:00:10Z	t1	10.92
2021-01-01T00:00:20Z	t1	7.35
2021-01-01T00:00:30Z	t1	17.53
2021-01-01T00:00:40Z	t1	15.23
2021-01-01T00:00:50Z	t1	4.43

_time	*tag	_value
2021-01-01T00:00:00Z	t2	19.85
2021-01-01T00:00:10Z	t2	4.97
2021-01-01T00:00:20Z	t2	-3.75
2021-01-01T00:00:30Z	t2	19.77
2021-01-01T00:00:40Z	t2	13.86
2021-01-01T00:00:50Z	t2	1.86

Output data

_time	_value	exp	frac	*tag
2021-01-01T00:00:00Z	-2.18	2	-0.545	t1
2021-01-01T00:00:10Z	10.92	4	0.6825	t1
2021-01-01T00:00:20Z	7.35	3	0.91875	t1
2021-01-01T00:00:30Z	17.53	5	0.5478125	t1
2021-01-01T00:00:40Z	15.23	4	0.951875	t1
2021-01-01T00:00:50Z	4.43	3	0.55375	t1

_time	_value	exp	frac	*tag
2021-01-01T00:00:00Z	19.85	5	0.6203125	t2
2021-01-01T00:00:10Z	4.97	3	0.62125	t2
2021-01-01T00:00:20Z	-3.75	2	-0.9375	t2
2021-01-01T00:00:30Z	19.77	5	0.6178125	t2
2021-01-01T00:00:40Z	13.86	4	0.86625	t2
2021-01-01T00:00:50Z	1.86	1	0.93	t2

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