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ATAN2 function

ATAN2 is a trigonometric function that returns the arc tangent of one number divided by another number. The return value is in radians and is between PI/2 and -PI/2.

Syntax

ATAN2(number1, number2)

Arguments

Return type

DOUBLE PRECISION

Examples

To return the arc tangent of 2/2 and multiply it by 4, use the following example.

SELECT ATAN2(2,2) * 4 AS PI;

+-------------------+
|        pi         |
+-------------------+
| 3.141592653589793 |
+-------------------+

To convert the arc tangent of 1/0 (which evaluates to 0) to the equivalent number of degrees, use the following example.

SELECT (ATAN2(1,0) * 180/(SELECT PI())) AS degrees;

+---------+
| degrees |
+---------+
|      90 |
+---------+