---
title: math.modf() function
description: >
  `math.modf()` returns integer and fractional floating-point numbers that sum to `f`.
menu:
  flux_v0_ref:
    name: math.modf
    parent: math
    identifier: math/modf
weight: 101
---

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`math.modf()` returns integer and fractional floating-point numbers that sum to `f`.

Both values have the same sign as `f`.

##### Function type signature

```js
(f: float) => {int: float, frac: float}
```

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

## Parameters

### f
({{< req >}})
Value to operate on.




## Examples

- [Return the integer and float that sum to a value](#return-the-integer-and-float-that-sum-to-a-value)
- [Use math.modf in map](#use-mathmodf-in-map)

### Return the integer and float that sum to a value

```js
import "math"

math.modf(f: 3.14)// {frac: 0.14000000000000012, int: 3}


```


### Use math.modf in map

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

sampledata.float()
    |> map(
        fn: (r) => {
            result = math.modf(f: r._value)

            return {_time: r._time, int: result.int, frac: result.frac}
        },
    )

```

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#### 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                | frac                 | int  |
| -------------------- | -------------------- | ---- |
| 2021-01-01T00:00:00Z | -0.18000000000000016 | -2   |
| 2021-01-01T00:00:10Z | 0.9199999999999999   | 10   |
| 2021-01-01T00:00:20Z | 0.34999999999999964  | 7    |
| 2021-01-01T00:00:30Z | 0.5300000000000011   | 17   |
| 2021-01-01T00:00:40Z | 0.23000000000000043  | 15   |
| 2021-01-01T00:00:50Z | 0.4299999999999997   | 4    |
| 2021-01-01T00:00:00Z | 0.8500000000000014   | 19   |
| 2021-01-01T00:00:10Z | 0.9699999999999998   | 4    |
| 2021-01-01T00:00:20Z | -0.75                | -3   |
| 2021-01-01T00:00:30Z | 0.7699999999999996   | 19   |
| 2021-01-01T00:00:40Z | 0.8599999999999994   | 13   |
| 2021-01-01T00:00:50Z | 0.8600000000000001   | 1    |

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