PHP: atan2 - Manual

downloads | documentation | faq | getting help | mailing lists | reporting bugs | php.net sites | links | conferences | my php.net

search for in the

atan asinh

Last updated: Fri, 26 Jan 2007

view this page in

# 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().

add a note User Contributed Notes
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. :)`
add a note
atan asinh

Last updated: Fri, 26 Jan 2007
show source | credits | stats | sitemap | contact | advertising | mirror sites
Copyright © 2001-2007 The PHP Group
All rights reserved.
This mirror generously provided by: Yahoo! Inc.
Last updated: Sat Mar 10 09:32:46 2007 PST