---
title: math.exp2() function
description: math.exp2() returns 2**x, the base-2 exponential of x.
url: https://docs.influxdata.com/flux/v0/stdlib/math/exp2/
estimated_tokens: 1409
product: Flux
version: v0
---

# math.exp2() function

-   Flux 0.22.0+
-   View InfluxDB support

`math.exp2()` returns `2**x`, the base-2 exponential 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 base-2 exponential of a value](#return-the-base-2-exponential-of-a-value)
-   [Use math.exp2 in map](#use-mathexp2-in-map)

### Return the base-2 exponential of a value

```js
import "math"

math.exp2(x: 21.0)// 2.097152e+06

```

### Use math.exp2 in map

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

sampledata.float()
    |> map(fn: (r) => ({r with _value: math.exp2(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 | 0.22067574907266369 | t1 |
| 2021-01-01T00:00:10Z | 1937.5260604940204 | t1 |
| 2021-01-01T00:00:20Z | 163.1437602968655 | t1 |
| 2021-01-01T00:00:30Z | 189258.68751552477 | t1 |
| 2021-01-01T00:00:40Z | 38431.45561643022 | t1 |
| 2021-01-01T00:00:50Z | 21.55573722985104 | t1 |

| _time | _value | *tag |
| --- | --- | --- |
| 2021-01-01T00:00:00Z | 945029.6050826148 | t2 |
| 2021-01-01T00:00:10Z | 31.341449522781655 | t2 |
| 2021-01-01T00:00:20Z | 0.07432544468767006 | t2 |
| 2021-01-01T00:00:30Z | 894052.4842704767 | t2 |
| 2021-01-01T00:00:40Z | 14868.793840716358 | t2 |
| 2021-01-01T00:00:50Z | 3.6300766212686435 | t2 |