atn2-transact-sql.md

title	ATN2 (Transact-SQL)
description	ATN2 (Transact-SQL)
author	markingmyname
ms.author	maghan
ms.date	07/24/2017
ms.service	sql
ms.subservice	t-sql
ms.topic	reference
ms.custom	ignite-2025
f1_keywords	ATN2 ATN2_TSQL
helpviewer_keywords	arctangent tangent ATN2 function
dev_langs	TSQL
monikerRange	>=aps-pdw-2016 || =azuresqldb-current || =azure-sqldw-latest || >=sql-server-2016 || >=sql-server-linux-2017 || =azuresqldb-mi-current || =fabric || =fabric-sqldb

ATN2 (Transact-SQL)

[!INCLUDE sql-asdb-asdbmi-asa-pdw-fabricse-fabricdw-fabricsqldb]

Returns the angle, in radians, between the positive x-axis and the ray from the origin to the point (y, x), where x and y are the values of the two specified float expressions.

:::image type="icon" source="../../includes/media/topic-link-icon.svg" border="false"::: Transact-SQL syntax conventions

Syntax

ATN2 ( float_expression , float_expression )  

Arguments

float_expression
An expression of data type float.

Return types

float

Examples

The following example calculates the ATN2 for the specified x and y components.

DECLARE @x FLOAT = 35.175643, @y FLOAT = 129.44;  
SELECT 'The ATN2 of the angle is: ' + CONVERT(VARCHAR, ATN2(@y, @x));  
GO  

[!INCLUDEssResult]

The ATN2 of the angle is: 1.30545                         
(1 row(s) affected)  

See also

CAST and CONVERT (Transact-SQL)
float and real (Transact-SQL)
Mathematical Functions (Transact-SQL)