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ATAN(3) FreeBSD Library Functions Manual ATAN(3)
NAME
atan, atanf, atanl - arc tangent functions of one variable
LIBRARY
Math Library (libm, -lm)
SYNOPSIS
#include <math.h>
double
atan(double x);
float
atanf(float x);
long double
atanl(long double x);
DESCRIPTION
The atan(), atanf(), and atanl() functions compute the principal value of
the arc tangent of x.
RETURN VALUES
These functions return the arc tangent in the range [-pi/2, +pi/2]
radians.
SEE ALSO
acos(3), asin(3), atan2(3), cos(3), cosh(3), math(3), sin(3), sinh(3),
tan(3), tanh(3)
STANDARDS
The atan(), atanf(), and atanl() functions conform to ISO/IEC 9899:1999
("ISO C99").
FreeBSD 14.0-RELEASE-p11 July 31, 2008 FreeBSD 14.0-RELEASE-p11