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

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---
title: math.cbrt() function
description: >
`math.cbrt()` returns the cube root of x.
menu:
flux_v0_ref:
name: math.cbrt
parent: math
identifier: math/cbrt
weight: 101
---
<!------------------------------------------------------------------------------
IMPORTANT: This page was generated from comments in the Flux source code. Any
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To make updates to this documentation, update the function comments above the
function definition in the Flux source code:
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Contributing to Flux: https://github.com/influxdata/flux#contributing
Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md
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`math.cbrt()` returns the cube root of x.
##### Function type signature
```js
(x: float) => float
```
{{% caption %}}
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
{{% /caption %}}
## Parameters
### x
({{< req >}})
Value to operate on.
## Examples
- [Return the cube root of a value](#return-the-cube-root-of-a-value)
- [Use math.cbrt in map](#use-mathcbrt-in-map)
### Return the cube root of a value
```js
import "math"
math.cbrt(x: 1728.0)// 12.0
```
### Use math.cbrt in map
```js
import "math"
import "sampledata"
sampledata.float()
|> map(fn: (r) => ({r with _value: math.cbrt(x: r._value)}))
```
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{{% 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 | 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 | *tag |
| -------------------- | ------------------ | ---- |
| 2021-01-01T00:00:00Z | -1.296638256974172 | t1 |
| 2021-01-01T00:00:10Z | 2.2185755003939347 | t1 |
| 2021-01-01T00:00:20Z | 1.9442962850073848 | t1 |
| 2021-01-01T00:00:30Z | 2.5977297737212623 | t1 |
| 2021-01-01T00:00:40Z | 2.478753275547562 | t1 |
| 2021-01-01T00:00:50Z | 1.6423582966480554 | t1 |
| _time | _value | *tag |
| -------------------- | ------------------- | ---- |
| 2021-01-01T00:00:00Z | 2.7076145363999617 | t2 |
| 2021-01-01T00:00:10Z | 1.7065491319882757 | t2 |
| 2021-01-01T00:00:20Z | -1.5536162529769295 | t2 |
| 2021-01-01T00:00:30Z | 2.703972205402708 | t2 |
| 2021-01-01T00:00:40Z | 2.402081527496116 | t2 |
| 2021-01-01T00:00:50Z | 1.2298089464641 | t2 |
{{% /expand %}}
{{< /expand-wrapper >}}