---
title: math.sqrt() function
description: math.sqrt() returns the square root of x.
url: https://docs.influxdata.com/flux/v0/stdlib/math/sqrt/
estimated_tokens: 1385
product: Flux
version: v0
---

# math.sqrt() function

-   Flux 0.22.0+
-   View InfluxDB support

`math.sqrt()` returns the square root of `x`.

##### Function type signature

```js
(x: float) => float
```

For more information, see [Function type signatures](/flux/v0/function-type-signatures/).

## Parameters

### x

(Required) Value to operate on.

## Examples

-   [Return the square root of a value](#return-the-square-root-of-a-value)
-   [Use math.sqrt in map](#use-mathsqrt-in-map)

### Return the square root of a value

```js
import "math"

math.sqrt(x: 4.0)// 2.0

```

### Use math.sqrt in map

```js
import "math"
import "sampledata"

sampledata.float()
    |> map(fn: (r) => ({r with _value: math.sqrt(x: r._value)}))
```

[](#view-example-input-and-output)

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 | NaN | t1 |
| 2021-01-01T00:00:10Z | 3.304542328371661 | t1 |
| 2021-01-01T00:00:20Z | 2.711088342345192 | t1 |
| 2021-01-01T00:00:30Z | 4.186884283091665 | t1 |
| 2021-01-01T00:00:40Z | 3.9025632602175713 | t1 |
| 2021-01-01T00:00:50Z | 2.1047565179849186 | t1 |

| _time | _value | *tag |
| --- | --- | --- |
| 2021-01-01T00:00:00Z | 4.455333881989093 | t2 |
| 2021-01-01T00:00:10Z | 2.2293496809607953 | t2 |
| 2021-01-01T00:00:20Z | NaN | t2 |
| 2021-01-01T00:00:30Z | 4.446346815083142 | t2 |
| 2021-01-01T00:00:40Z | 3.722902093797257 | t2 |
| 2021-01-01T00:00:50Z | 1.3638181696985856 | t2 |