stateCount() function

stateCount() returns the number of consecutive rows in a given state.

The state is defined by the fn predicate function. For each consecutive record that evaluates to true, the state count is incremented. When a record evaluates to false, the value is set to -1 and the state count is reset. If the record generates an error during evaluation, the point is discarded, and does not affect the state count. The state count is added as an additional column to each record.

Function type signature

(<-tables: stream[A], fn: (r: A) => bool, ?column: string) => stream[B] where A: Record, B: Record

Parameters

fn

(Required) Predicate function that identifies the state of a record.

column

Column to store the state count in. Default is stateCount.

tables

Input data. Default is piped-forward data (<-).

Examples

Count the number rows in a specific state

import "sampledata"

sampledata.int()
    |> stateCount(fn: (r) => r._value < 10)