The atan2() function returns the arc tangent of two variables.
Syntax
atan2(val1, val2)
Parameters
val1 − The dividend
val2 − The divisor
Return
The atan2() function returns the arc tangent of val2/ val1 in radians. The returned value is between -Pi and Pi.
Example
<?php echo(atan2(30,30) . "<br>"); echo(atan2(2,2) . "<br>"); ?>
Output
0.78539816339745<br>0.78539816339745<br>
Example
Let us see another example −
<?php echo(atan2(-15,-15) . "<br>"); echo(atan2(-0.90,-0.70) . "<br>"); ?>
Output
-2.3561944901923<br>-2.2318394956456<br>