% This is generated by ESQL's AbstractFunctionTestCase. Do not edit it. See ../README.md for how to regenerate it.

## Parameters

`field`
:   Expression that calculates the y-axis value of the sparkline graph for each datapoint.

`key`
:   Date expression from which to derive buckets.

`buckets`
:   Target number of buckets, or desired bucket size if `from` and `to` parameters are omitted.

`from`
:   Start of the range. Can be a date or a date expressed as a string.

`to`
:   End of the range. Can be a date or a date expressed as a string.

