elasticsearch/docs/reference/query-languages/esql/_snippets/functions/acos.md

ACOS [esql-acos]

Syntax

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Parameters

number

Number between -1 and 1. If null, the function returns null.

Description

Returns the arccosine of n as an angle, expressed in radians.

Supported types

number	result
double	double
integer	double
long	double
unsigned_long	double

Example

ROW a=.9
| EVAL acos=ACOS(a)

a:double	acos:double
.9	0.45102681179626236