stddev() function

The stddev() function computes the standard deviation of non-null records in a specified column.

Function type: Aggregate
Output data type: Float

stddev(
  column: "_value",
  mode: "sample"
)

Parameters

column

The column on which to operate. Defaults to "_value".

Data type: String

mode

The standard deviation mode or type of standard deviation to calculate. Defaults to "sample".

Data type: String

The available options are:

sample

Calculates the sample standard deviation where the data is considered to be part of a larger population.

population

Calculates the population standard deviation where the data is considered a population of its own.

Examples

from(bucket: "example-bucket")
  |> range(start: -5m)
  |> filter(fn: (r) =>
    r._measurement == "cpu" and
    r._field == "usage_system"
  )
  |> stddev()