docs-v2/content/flux/v0/stdlib/experimental/spread.md

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---
title: experimental.spread() function
description: >
`experimental.spread()` returns the difference between the minimum and maximum values in the
`_value` column for each input table.
menu:
flux_v0_ref:
name: experimental.spread
parent: experimental
identifier: experimental/spread
weight: 101
flux/v0/tags: [transformations, aggregates]
introduced: 0.107.0
---
<!------------------------------------------------------------------------------
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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------------------------------------------------------------------------------->
`experimental.spread()` returns the difference between the minimum and maximum values in the
`_value` column for each input table.
##### Function type signature
```js
(<-tables: stream[{A with _value: B}]) => stream[{A with _value: B}] where B: Numeric
```
{{% caption %}}
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
{{% /caption %}}
## Parameters
### tables
Input data. Default is piped-forward data (`<-`).
## Examples
### Return the difference between minimum and maximum values
```js
import "experimental"
import "sampledata"
sampledata.float()
|> experimental.spread()
```
{{< expand-wrapper >}}
{{% 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
| *tag | _value |
| ---- | ------- |
| t1 | 19.71 |
| *tag | _value |
| ---- | ------- |
| t2 | 23.6 |
{{% /expand %}}
{{< /expand-wrapper >}}