groupArrayMovingAvg

Introduced in: v20.1.0

Calculates the moving average of input values.

Syntax

groupArrayMovingAvg(numbers_for_summing)
groupArrayMovingAvg(window_size)(numbers_for_summing)

Parameters

window_size — Size of the calculation window. If left unspecified, the function takes the window size equal to the number of rows in the column. UInt64

Arguments

numbers_for_summing — Expression resulting in a numeric data type value. (U)Int* or Float* or Decimal

Returned value

Returns an array of the same size as the input data. For non-Decimal input, the array contains Float64 values. For Decimal input, the array contains Decimal values with the input scale. Array

Examples

Usage example

CREATE TABLE t
(
    `int` UInt8,
    `float` Float32,
    `dec` Decimal32(2)
)
ENGINE = Memory;

INSERT INTO t VALUES (1, 1.1, 1.10), (2, 2.2, 2.20), (4, 4.4, 4.40), (7, 7.77, 7.77);

SELECT
    groupArrayMovingAvg(int) AS I,
    groupArrayMovingAvg(float) AS F,
    groupArrayMovingAvg(dec) AS D
FROM t;

┌─I────────────────────┬─F─────────────────────────────────────────────────────────────────────────────┬─D─────────────────────┐
│ [0.25,0.75,1.75,3.5] │ [0.2750000059604645,0.8250000178813934,1.9250000417232513,3.8675000369548798] │ [0.27,0.82,1.92,3.86] │
└──────────────────────┴───────────────────────────────────────────────────────────────────────────────┴───────────────────────┘

With window size

SELECT
    groupArrayMovingAvg(2)(int) AS I,
    groupArrayMovingAvg(2)(float) AS F,
    groupArrayMovingAvg(2)(dec) AS D
FROM t;

┌─I───────────────┬─F───────────────────────────────────────────────────────────────────────────┬─D────────────────────┐
│ [0.5,1.5,3,5.5] │ [0.550000011920929,1.6500000357627869,3.3000000715255737,6.085000038146973] │ [0.55,1.65,3.3,6.08] │
└─────────────────┴─────────────────────────────────────────────────────────────────────────────┴──────────────────────┘