134 lines
3.5 KiB
Markdown
134 lines
3.5 KiB
Markdown
---
|
|
title: string() function
|
|
description: >
|
|
`string()` converts a value to a string type.
|
|
menu:
|
|
flux_v0_ref:
|
|
name: string
|
|
parent: universe
|
|
identifier: universe/string
|
|
weight: 101
|
|
flux/v0/tags: [type-conversions]
|
|
introduced: 0.7.0
|
|
---
|
|
|
|
<!------------------------------------------------------------------------------
|
|
|
|
IMPORTANT: This page was generated from comments in the Flux source code. Any
|
|
edits made directly to this page will be overwritten the next time the
|
|
documentation is generated.
|
|
|
|
To make updates to this documentation, update the function comments above the
|
|
function definition in the Flux source code:
|
|
|
|
https://github.com/influxdata/flux/blob/master/stdlib/universe/universe.flux#L3351-L3351
|
|
|
|
Contributing to Flux: https://github.com/influxdata/flux#contributing
|
|
Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md
|
|
|
|
------------------------------------------------------------------------------->
|
|
|
|
`string()` converts a value to a string type.
|
|
|
|
|
|
|
|
##### Function type signature
|
|
|
|
```js
|
|
(v: A) => string
|
|
```
|
|
|
|
{{% caption %}}
|
|
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
|
|
{{% /caption %}}
|
|
|
|
## Parameters
|
|
|
|
### v
|
|
({{< req >}})
|
|
Value to convert.
|
|
|
|
|
|
|
|
|
|
## Examples
|
|
|
|
- [Convert basic types to strings](#convert-basic-types-to-strings)
|
|
- [Convert all values in a column to strings](#convert-all-values-in-a-column-to-strings)
|
|
|
|
### Convert basic types to strings
|
|
|
|
```js
|
|
string(v: true)
|
|
// Returns "true"
|
|
|
|
string(v: 1m)
|
|
// Returns "1m"
|
|
|
|
string(v: 2021-01-01T00:00:00Z)
|
|
// Returns "2021-01-01T00:00:00Z"
|
|
|
|
string(v: 10.12)
|
|
// Returns "10.12"
|
|
```
|
|
|
|
|
|
### Convert all values in a column to strings
|
|
|
|
If converting the `_value` column to string types, use `toString()`.
|
|
If converting columns other than `_value`, use `map()` to iterate over each
|
|
row and `string()` to convert a column value to a string type.
|
|
|
|
```js
|
|
data
|
|
|> map(fn: (r) => ({r with exampleCol: string(v: r.exampleCol)}))
|
|
|
|
```
|
|
|
|
{{< expand-wrapper >}}
|
|
{{% expand "View example input and output" %}}
|
|
|
|
#### Input data
|
|
|
|
| _time | *tag | exampleCol |
|
|
| -------------------- | ---- | ----------- |
|
|
| 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 | exampleCol |
|
|
| -------------------- | ---- | ----------- |
|
|
| 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 | exampleCol | *tag |
|
|
| -------------------- | ----------- | ---- |
|
|
| 2021-01-01T00:00:00Z | -2.18 | t1 |
|
|
| 2021-01-01T00:00:10Z | 10.92 | t1 |
|
|
| 2021-01-01T00:00:20Z | 7.35 | t1 |
|
|
| 2021-01-01T00:00:30Z | 17.53 | t1 |
|
|
| 2021-01-01T00:00:40Z | 15.23 | t1 |
|
|
| 2021-01-01T00:00:50Z | 4.43 | t1 |
|
|
|
|
| _time | exampleCol | *tag |
|
|
| -------------------- | ----------- | ---- |
|
|
| 2021-01-01T00:00:00Z | 19.85 | t2 |
|
|
| 2021-01-01T00:00:10Z | 4.97 | t2 |
|
|
| 2021-01-01T00:00:20Z | -3.75 | t2 |
|
|
| 2021-01-01T00:00:30Z | 19.77 | t2 |
|
|
| 2021-01-01T00:00:40Z | 13.86 | t2 |
|
|
| 2021-01-01T00:00:50Z | 1.86 | t2 |
|
|
|
|
{{% /expand %}}
|
|
{{< /expand-wrapper >}}
|