MySQL ATAN() Function

The ATAN() function in MySQL calculates the arctangent (inverse tangent) of a number. The arctangent is the angle whose tangent is equal to the given number. The result is an angle expressed in radians.

ATAN(): Definition and Usage

ATAN() has two forms: one that takes a single number and another that takes two numbers. The single-number form calculates the arctangent of that number. The two-number form calculates the arctangent of the ratio of the two numbers, providing a more versatile way to compute angles, especially when dealing with Cartesian coordinates (x, y).

Syntax


ATAN(number) -- Single-number form
ATAN(a, b) -- Two-number form

Parameter Values

Parameter	Description
`number`	A numeric value representing the tangent of an angle (single-number form).
`a, b`	Two numeric values; the arctangent of (a/b) is calculated (two-number form).

Examples

Arctangent of a Single Number

This example finds the arctangent of 2.5.

Syntax


SELECT ATAN(2.5);

Output


1.19028994968263 (Result in radians)

Arctangent of Two Numbers

This example demonstrates the two-number form. The arctangent of (-0.8/2) is calculated.

Syntax


SELECT ATAN(-0.8, 2);

Output


-0.38050637711219 (Result in radians)