avg()

Calculates the arithmetic mean of numeric values in a group.

Syntax

avg(EXPR)

Parameters

EXPR
An expression that returns a numeric value to average.

Description

The avg() function accumulates the sum and count of numeric values returned by EXPR as it processes records in a group. Null values and non-numeric values are excluded from aggregation. It handles both integer types (integer, long) and floating-point types (float, double).

When aggregation is complete, the function returns the sum divided by the count as a 64-bit floating-point number (double). If there are no values to aggregate, it returns null.

This function can only be used in aggregation commands such as stats and timechart.

Error codes

CodeDescription
91020The number of arguments is wrong.

Usage examples

To prepare the WEB_APACHE_SAMPLE table used in these examples, refer to Preparing sample data.

  1. Calculate the average response size for all requests

    table WEB_APACHE_SAMPLE | stats avg(bytes)

  2. Calculate the average response size per HTTP method

    table WEB_APACHE_SAMPLE | stats avg(bytes) by method

  3. Null value handling

    json "[{'val': 10}, {'val': null}, {'val': 30}]"
| stats avg(val)
| # avg(val): 20.0

Compatibility

The avg() function has been available since before Logpresso Sonar 4.0.