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

title	description	menu	weight
math.isInf() function	`math.isInf()` reports whether `f` is an infinity, according to `sign`.	flux_v0_ref name parent identifier math.isInf math math/isInf	101

math.isInf() reports whether f is an infinity, according to sign.

If sign > 0, math.isInf reports whether f is positive infinity. If sign < 0, math.isInf reports whether f is negative infinity. If sign == 0, math.isInf reports whether f is either infinity.

Function type signature

(f: float, sign: int) => bool

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

Parameters

f

({{< req >}}) is the value used in the evaluation.

sign

({{< req >}}) is the sign used in the evaluation.

Examples

• Test if a value is an infinity value
• Use math.isInf in map

Test if a value is an infinity value

import "math"

math.isInf(f: 2.12, sign: 3)// false

Use math.isInf in map

import "math"

data
    |> map(fn: (r) => ({r with _value: math.isInf(f: r._value, sign: 1)}))

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

Input data

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

_time	*tag	_value
2021-01-01T00:00:00Z	t2	+Inf
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	+Inf
2021-01-01T00:00:50Z	t2	1.86

Output data

_time	_value	*tag
2021-01-01T00:00:00Z	false	t1
2021-01-01T00:00:10Z	true	t1
2021-01-01T00:00:20Z	false	t1
2021-01-01T00:00:30Z	true	t1
2021-01-01T00:00:40Z	true	t1
2021-01-01T00:00:50Z	false	t1

_time	_value	*tag
2021-01-01T00:00:00Z	true	t2
2021-01-01T00:00:10Z	false	t2
2021-01-01T00:00:20Z	false	t2
2021-01-01T00:00:30Z	false	t2
2021-01-01T00:00:40Z	true	t2
2021-01-01T00:00:50Z	false	t2

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