Influxdata
/
docs-v2
mirror of https://github.com/influxdata/docs-v2.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

upated holtWinters doc to address PR feedback

pull/372/head
Scott Anderson 2019-08-06 16:36:46 -06:00
parent ba7bcd6452
commit 6a85f883b4
1 changed files with 12 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
content/v2.0/reference/flux/functions/built-in/transformations/aggregates/holtwinters.md
View File

@ -36,24 +36,25 @@ values six minutes apart.
#### Seasonality #### Seasonality
[`seasonality`](#seasonality) delimits the length of a seasonal pattern according to `interval`. [`seasonality`](#seasonality) delimits the length of a seasonal pattern according to `interval`.
If your `interval` is `2m` and `s` is `3`, then the seasonal pattern occurs every If your `interval` is `2m` and `seasonality` is `4`, then the seasonal pattern occurs every
six minutes or every three data points. eight minutes or every four data points.
If there is no seasonality in the data, set `seasonality` to `0`. If data doesn't have a seasonal pattern, set `seasonality` to `0`.
#### Space values evenly in time #### Space values evenly in time
`holtWinters()` expects values evenly spaced in time. `holtWinters()` expects values evenly spaced in time.
To ensure this, it applies the following rules: To ensure `holtWinters()` values are spaced evenly in time, the following rules apply:
- `interval` is used to divide the into buckets based time. - Data is grouped into time-based "buckets" determined by the `interval`.
- If a bucket includes many values, the first value is used. - If a bucket includes many values, the first value is used.
- If a bucket includes no values, a missing value (`null`) is added for that bucket. - If a bucket includes no values, a missing value (`null`) is added for that bucket.
By default, `holtWinters()` uses the first value in each time bucket. By default, `holtWinters()` uses the first value in each time bucket to run the Holt-Winters calculation.
Use [`window()`](/v2.0/reference/flux/functions/built-in/transformations/window/) To specify other values to use in the calculation, use:
and [selectors](/v2.0/reference/flux/functions/built-in/transformations/selectors/)
or [aggregates](/v2.0/reference/flux/functions/built-in/transformations/aggregates/), - [`window()`](/v2.0/reference/flux/functions/built-in/transformations/window/)
or use [`aggregateWindow()`](/v2.0/reference/flux/functions/built-in/transformations/aggregates/aggregatewindow) with [selectors](/v2.0/reference/flux/functions/built-in/transformations/selectors/)
to specify other values to use in the `holtWinters()` calculation. or [aggregates](/v2.0/reference/flux/functions/built-in/transformations/aggregates/)
- [`aggregateWindow()`](/v2.0/reference/flux/functions/built-in/transformations/aggregates/aggregatewindow)
#### Fitted model #### Fitted model
The `holtWinters()` function applies the [Nelder-Mead optimization](https://en.wikipedia.org/wiki/Nelder%E2%80%93Mead_method) The `holtWinters()` function applies the [Nelder-Mead optimization](https://en.wikipedia.org/wiki/Nelder%E2%80%93Mead_method)
@ -65,7 +66,6 @@ to include "fitted" data points in results when [`withFit`](#withfit) is set to
#### Null values #### Null values
`holtWinters()` treats `null` values as missing data points and includes them in the Holt-Winters calculation. `holtWinters()` treats `null` values as missing data points and includes them in the Holt-Winters calculation.
## Parameters ## Parameters
### n ### n