FREE Web Template Download
HTML CSS JAVASCRIPT SQL PHP BOOTSTRAP JQUERY ANGULARJS TUTORIALS REFERENCES EXAMPLES Blog
 

PHP atan2() Function

PHP Math Reference PHP Math Reference

Example

Return the arc tangent of two variables with the atan2() function:

<?php
echo(atan2(0.50,0.50) . "<br>");
echo(atan2(-0.50,-0.50) . "<br>");
echo(atan2(5,5) . "<br>");
echo(atan2(10,20) . "<br>");
echo(atan2(-5,-5) . "<br>");
echo(atan2(-10,10));
?>
Run example »

Definition and Usage

The atan2() function returns the arc tangent of two variables x and y.


Syntax

atan2(y,x);

Parameter Description
y Required. Specifies the dividend
x Required. Specifies the divisor

Technical Details

Return Value: The arc tangent of y/x in radians, which is between -Pi and Pi
Return Type: Float
PHP Version: 4+

PHP Math Reference PHP Math Reference