79 lines
1.6 KiB
Markdown
79 lines
1.6 KiB
Markdown
---
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title: math.log() function
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description: >
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`math.log()` returns the natural logarithm of `x`.
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menu:
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flux_v0_ref:
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name: math.log
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parent: math
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identifier: math/log
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weight: 101
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---
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<!------------------------------------------------------------------------------
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IMPORTANT: This page was generated from comments in the Flux source code. Any
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edits made directly to this page will be overwritten the next time the
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documentation is generated.
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To make updates to this documentation, update the function comments above the
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function definition in the Flux source code:
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https://github.com/influxdata/flux/blob/master/stdlib/math/math.flux#L1384-L1384
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Contributing to Flux: https://github.com/influxdata/flux#contributing
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Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md
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------------------------------------------------------------------------------->
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`math.log()` returns the natural logarithm of `x`.
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##### Function type signature
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```js
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(x: float) => float
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```
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{{% caption %}}
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For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
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{{% /caption %}}
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## Parameters
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### x
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({{< req >}})
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Value to operate on.
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## Examples
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- [Return the natural logarithm of a value](#return-the-natural-logarithm-of-a-value)
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- [Use math.log in map](#use-mathlog-in-map)
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### Return the natural logarithm of a value
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```js
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import "math"
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math.log(x: 3.14)// 1.144222799920162
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```
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### Use math.log in map
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```js
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import "sampledata"
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import "math"
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sampledata.float()
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|> map(fn: (r) => ({r with _value: math.log(x: r._value)}))
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```
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