ATAN(3)                   OpenBSD Programmer's Manual                  ATAN(3)

NAME
     atan, atanf - arc tangent functions of one variable

SYNOPSIS
     #include <math.h>

     double
     atan(double x);

     float
     atanf(float x);

DESCRIPTION
     The atan() function computes the principal value of the arc tangent of x
     in the range [-pi/2, +pi/2].  The atanf() function is a single precision
     version of atan().

SEE ALSO
     acos(3), asin(3), atan2(3), cos(3), cosh(3), math(3), sin(3), sinh(3),
     tan(3), tanh(3)

OpenBSD 3.5                       May 2, 1991                                1
