docs-v2/content/flux/v0/stdlib/generate/from.md

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---
title: generate.from() function
description: >
`generate.from()` generates data using the provided parameter values.
menu:
flux_v0_ref:
name: generate.from
parent: generate
identifier: generate/from
weight: 101
flux/v0/tags: [inputs]
---
<!------------------------------------------------------------------------------
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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Contributing to Flux: https://github.com/influxdata/flux#contributing
Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md
------------------------------------------------------------------------------->
`generate.from()` generates data using the provided parameter values.
##### Function type signature
```js
(count: int, fn: (n: int) => int, start: A, stop: A) => stream[{_value: int, _time: time, _stop: time, _start: time}] where A: Timeable
```
{{% caption %}}
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
{{% /caption %}}
## Parameters
### count
({{< req >}})
Number of rows to generate.
### fn
({{< req >}})
Function used to generate values.
The function takes an `n` parameter that represents the row index, operates
on `n`, and then returns an integer value. Rows use zero-based indexing.
### start
({{< req >}})
Beginning of the time range to generate values in.
### stop
({{< req >}})
End of the time range to generate values in.
## Examples
### Generate sample data
```js
import "generate"
generate.from(
count: 6,
fn: (n) => (n + 1) * (n + 2),
start: 2021-01-01T00:00:00Z,
stop: 2021-01-02T00:00:00Z,
)
```