ATAN(3) Linux Programmer's Manual ATAN(3)NAME
atan, atanf, atanl - arc tangent function
SYNOPSIS
#include <math.h>
double atan(double x);
float atanf(float x);
long double atanl( long double x);
Link with -lm.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
atanf(), atanl():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
or cc -std=c99
DESCRIPTION
The atan() function calculates the principal value of the arc tangent of x; that is the value whose tangent is x.
RETURN VALUE
On success, these functions return the principal value of the arc tangent of x in radians; the return value is in the range [-pi/2, pi/2].
If x is a NaN, a NaN is returned.
If x is +0 (-0), +0 (-0) is returned.
If x is positive infinity (negative infinity), +pi/2 (-pi/2) is returned.
ERRORS
No errors occur.
CONFORMING TO
C99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD, C89.
SEE ALSO acos(3), asin(3), atan2(3), carg(3), catan(3), cos(3), sin(3), tan(3)COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
2010-09-20 ATAN(3)
Check Out this Related Man Page
ATAN(3) Linux Programmer's Manual ATAN(3)NAME
atan, atanf, atanl - arc tangent function
SYNOPSIS
#include <math.h>
double atan(double x);
float atanf(float x);
long double atanl( long double x);
Link with -lm.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
atanf(), atanl():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
or cc -std=c99
DESCRIPTION
The atan() function calculates the principal value of the arc tangent of x; that is the value whose tangent is x.
RETURN VALUE
On success, these functions return the principal value of the arc tangent of x in radians; the return value is in the range [-pi/2, pi/2].
If x is a NaN, a NaN is returned.
If x is +0 (-0), +0 (-0) is returned.
If x is positive infinity (negative infinity), +pi/2 (-pi/2) is returned.
ERRORS
No errors occur.
CONFORMING TO
C99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD, C89.
SEE ALSO acos(3), asin(3), atan2(3), carg(3), catan(3), cos(3), sin(3), tan(3)COLOPHON
This page is part of release 3.44 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
2010-09-20 ATAN(3)
Help!!
Anybody out there had much to do with setting up SATAN (Security Admin Tool for Analyzing Networks)?
I need help setting it up on a Linux box. (1 Reply)
has anyone had any experience with SATAN? and can fill me in with some quick pro/cons and maybe some screenshots?
thanks
email removed - read the rules (1 Reply)
Hello All,
I need your help in the following situation. I have a 100x100 matrix with angle values ranging from -180 to 180. I would like to calculate the atan2 values for the above mentioned matrix, and the output should be in the same format (100x100 matrix).
I tried the following code:
... (3 Replies)