atn2-transact-sql.md

description	ATN2 (Transact-SQL)
title	ATN2 (Transact-SQL) | Microsoft Docs
ms.custom
ms.date	07/24/2017
ms.prod	sql
ms.prod_service	database-engine, sql-database, sql-data-warehouse, pdw
ms.reviewer
ms.technology	t-sql
ms.topic	reference
f1_keywords	ATN2 ATN2_TSQL
dev_langs	TSQL
helpviewer_keywords	arctangent tangent ATN2 function
ms.assetid	014b291e-7cd7-4c39-b20d-5db3a9f0505d
author	cawrites
ms.author	chadam
monikerRange	>=aps-pdw-2016||=azuresqldb-current||=azure-sqldw-latest||>=sql-server-2016||>=sql-server-linux-2017||=azuresqldb-mi-current

ATN2 (Transact-SQL)

[!INCLUDE sql-asdb-asdbmi-asa-pdw]

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.

Transact-SQL Syntax Conventions

Syntax

ATN2 ( float_expression , float_expression )  

[!INCLUDEsql-server-tsql-previous-offline-documentation]

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)