atan2

(PHP 3 >= 3.0.5, PHP 4, PHP 5)

atan2 -- Arc tangent of two variables

Description

float atan2 ( float y, float x )

This function calculates the arc tangent of the two variables x and y. It is similar to calculating the arc tangent of y / x, except that the signs of both arguments are used to determine the quadrant of the result.

The function returns the result in radians, which is between -PI and PI (inclusive).

See also acos() and atan().



atan2
reubs at idsdatanet dot com
23-May-2003 01:01
Just a note:

PHP's atan2 function receives parameters in (y,x) and Excel receives it in (x,y) format. Just in case you are porting formulas across. :)

<asinhatan>
 Last updated: Tue, 15 Nov 2005