SQL Server - ATAN() Function

The SQL Server (Transact-SQL) ATAN() function returns arc tangent of a value. The returned value will be in the range -𝜋/2 through 𝜋/2.

Note: ATAN() is the inverse of TAN().

Syntax

ATAN(x)

Parameters

`x`	`Required.` Specify the value.

Return Value

Returns the arc tangent of the value.

Example 1:

The example below shows the usage of ATAN() function.

SELECT ATAN(3);
Result: 1.2490457723982544

SELECT ATAN(0.5);
Result: 0.4636476090008061

SELECT ATAN(0);
Result: 0

SELECT ATAN(-0.5);
Result: -0.4636476090008061

SELECT ATAN(-3);
Result: -1.2490457723982544

Example 2:

Consider a database table called Sample with the following records:

Data	x
Data 1	-1
Data 2	-0.5
Data 3	0
Data 4	0.5
Data 5	1

The statement given below can be used to calculate the arc tangent of records of column x.

SELECT *, ATAN(x) AS ATAN_Value FROM Sample;

This will produce the result as shown below:

Data	x	ATAN_Value
Data 1	-1	-0.7853981633974483
Data 2	-0.5	-0.4636476090008061
Data 3	0	0
Data 4	0.5	0.4636476090008061
Data 5	1	0.7853981633974483

❮ SQL Server Functions