content/flux/v0/stdlib/math/isnan.md
math.isNaN() reports whether f is an IEEE 754 "not-a-number" value.
(f: float) => bool
{{% caption %}} For more information, see Function type signatures. {{% /caption %}}
({{< req >}}) Value to operate on.
import "math"
math.isNaN(f: 12.345)// false
import "math"
data
|> map(fn: (r) => ({r with _value: math.isNaN(f: r._value)}))
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| _time | *tag | _value |
|---|---|---|
| 2021-01-01T00:00:00Z | t1 | -2.18 |
| 2021-01-01T00:00:10Z | t1 | NaN |
| 2021-01-01T00:00:20Z | t1 | 7.35 |
| 2021-01-01T00:00:30Z | t1 | NaN |
| 2021-01-01T00:00:40Z | t1 | NaN |
| 2021-01-01T00:00:50Z | t1 | 4.43 |
| _time | *tag | _value |
|---|---|---|
| 2021-01-01T00:00:00Z | t2 | NaN |
| 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 | NaN |
| 2021-01-01T00:00:50Z | t2 | 1.86 |
| _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 >}}