atan2 man page on OpenDarwin

Man page or keyword search:  
man Server   3202 pages
apropos Keyword Search (all sections)
Output format
OpenDarwin logo
[printable version]

ATAN2(3)		 BSD Library Functions Manual		      ATAN2(3)

     atan2 — arc tangent function of two variables

     #include <math.h>

     atan2(double y, double x);

     The atan2() function computes the principal value of the arc tangent of
     y/x, using the signs of both arguments to determine the quadrant of the
     return value.

     atan2(�0, -0) returns �pi.

     atan2(�0, +0) returns �0.

     atan2(�0, x) returns �pi for x < 0.

     atan2(�0, x) returns �0 for x > 0.

     atan2(y, �0) returns -pi/2 for y > 0.

     atan2(�y, -infinity) returns �pi for finite y > 0.

     atan2(�y, +infinity) returns �0 for finite y > 0.

     atan2(�infinity, +x) returns �pi/2 for finite x.

     atan2(�infinity, -infinity) returns �3*pi/4.

     atan2(�infinity, +infinity) returns �pi/4.

     The atan2() function is used mostly to convert from rectangular (x,y) to
     polar (r,theta) coordinates that must satisfy x = r∗cos theta and y =
     r∗sin theta.  In general, conversions to polar coordinates should be com‐
     puted thus:

	   r	:= hypot(x,y);	... := sqrt(x∗x+y∗y)
	   theta     := atan2(y,x).

     acos(3), asin(3), atan(3), cos(3), cosh(3), sin(3), sinh(3), tan(3),
     tanh(3), math(3),

     The atan2() function conforms to ISO/IEC 9899:1999(E).

BSD			       November 18, 2002			   BSD

List of man pages available for OpenDarwin

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
Vote for polarhome
Free Shell Accounts :: the biggest list on the net