Flux aggregate functions

Warning! This page documents an earlier version of Flux, which is no longer actively developed. Flux v0.50 is the most recent stable version of Flux.

Flux aggregate functions take values from an input table and aggregate them in some way. The output table contains is a single row with the aggregated value.

Aggregate operations output a table for every input table they receive. A column to aggregate must be provided to the operation. Any output table will have the following properties:

  • It always contains a single record.
  • It will have the same group key as the input table.
  • It will contain a column for the provided aggregate column. The column label will be the same as the input table. The type of the column depends on the specific aggregate operation. The value of the column will be null if the input table is empty or the input column has only null values.
  • It will not have a _time column.

aggregateWindow helper function

The aggregateWindow() function does most of the work needed when aggregating data. It windows and aggregates the data, then combines windowed tables into a single output table.

Aggregate functions

The following aggregate functions are available:

Aggregate selectors

The following functions are both aggregates and selectors. Each returns n values after performing an aggregate operation. They are categorized as selector functions in this documentation: