PHP: atan2() function

Last update on August 19 2022 21:50:39 (UTC/GMT +8 hours)

Description

The atan2() function is used to calculate the arc tangent of the two variables.

Version:

(PHP 4 and above)

Syntax:

atan2( ny, nx )

Parameters:

Name	Description	Required / Optional	Type
nx	Divisor number	Required	Float
ny	Dividend number	Required	Float

Return value:

The arc tangent of ny/nx in radians.

Value Type: Float.

Pictorial Presentation:

Example:

<?php
echo(atan2(0.45,0.45) . "<br />");
echo(atan2(-0.40,-0.40) . "<br />");
echo(atan2(6,7) . "<br />");
echo(atan2(15,30) . "<br />");
echo(atan2(-6,-6) . "<br />");
echo(atan2(-20,20))
?>

Output:

0.785398163397
-2.35619449019
0.708626272128
0.463647609001
-2.35619449019
-0.785398163397

View the example in the browser