---
title: math.ceil() function
description: >
  `math.ceil()` returns the least integer value greater than or equal to `x`.
menu:
  flux_v0_ref:
    name: math.ceil
    parent: math
    identifier: math/ceil
weight: 101
---

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`math.ceil()` returns the least integer value greater than or equal to `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

- [Round a value up to the nearest integer](#round-a-value-up-to-the-nearest-integer)
- [Use math.ceil in map](#use-mathceil-in-map)

### Round a value up to the nearest integer

```js
import "math"

math.ceil(x: 3.14)// 4.0


```


### Use math.ceil in map

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

sampledata.float()
    |> map(fn: (r) => ({r with _value: math.ceil(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 | -2      | t1   |
| 2021-01-01T00:00:10Z | 11      | t1   |
| 2021-01-01T00:00:20Z | 8       | t1   |
| 2021-01-01T00:00:30Z | 18      | t1   |
| 2021-01-01T00:00:40Z | 16      | t1   |
| 2021-01-01T00:00:50Z | 5       | t1   |

| _time                | _value  | *tag |
| -------------------- | ------- | ---- |
| 2021-01-01T00:00:00Z | 20      | t2   |
| 2021-01-01T00:00:10Z | 5       | t2   |
| 2021-01-01T00:00:20Z | -3      | t2   |
| 2021-01-01T00:00:30Z | 20      | t2   |
| 2021-01-01T00:00:40Z | 14      | t2   |
| 2021-01-01T00:00:50Z | 2       | t2   |

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