content/flux/v0/stdlib/experimental/stddev.md
experimental.stddev() returns the standard deviation of non-null values in the _value
column for each input table.
The following modes are available when calculating the standard deviation of data.
Calculate the sample standard deviation where the data is considered to be part of a larger population.
Calculate the population standard deviation where the data is considered a population of its own.
(<-tables: stream[{A with _value: float}], ?mode: string) => stream[{A with _value: float}]
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Standard deviation mode or type of standard deviation to calculate.
Default is sample.
Available options:
Input data. Default is piped-forward data (<-).
import "experimental"
import "sampledata"
sampledata.float()
|> experimental.stddev()
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| _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 |
| *tag | _value |
|---|---|
| t1 | 7.263244454099008 |
| *tag | _value |
|---|---|
| t2 | 9.85926704510364 |
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