trig(3M)                                                           trig(3M)

NAME
     trig: sin, sinf, cos, cosf, tan, tanf, asin, asinf, acos, acosf, atan,
     atanf, atan2, atan2f - trigonometric functions

SYNOPSIS
     cc [flag ...] file ... -lm [library ...]

     cc -O -Ksd [flag ...] file ... -J sfm [library ...]

     #include <math.h>

     double sin(double x);

     float sinf(float x);

     double cos(double x);

     float cosf(float x);

     double tan(double x);

     float tanf(float x);

     double asin(double x);

     float asinf(float x);

     double acos(double x);

     float acosf(float x);

     double atan(double x);

     float atanf(float x);

     double atan2(double y, double x);

     float atan2f(float y, float x);

DESCRIPTION
     sin(), cos(), and tan() and the single-precision versions sinf(),
     cosf(), and tanf() return, respectively, the sine, cosine, and tangent
     of their argument, x, measured in radians.

     asin() and asinf() return the arcsine of x, in the range
     [-pi/2,+pi/2].

     acos() and acosf() return the arccosine of x, in the range [0,+pi].

     atan() and atanf() return the arctangent of x, in the range
     [-pi/2,+pi/2].




Page 1                       Reliant UNIX 5.44                Printed 11/98

trig(3M)                                                           trig(3M)

     atan2() and atan2f() return the arctangent of y/x, in the range
     [-pi,+pi], using the signs of both arguments to determine the quadrant
     of the return value.

RESULT
     If the magnitude of the argument of asin(), asinf(), acos(), or
     acosf() is greater than 1, or if both arguments of atan2() or atan2f()
     are 0, 0 is returned and errno is set to EDOM. In addition, a message
     indicating DOMAIN error is output on standard error.

NOTES
     The functions sinf(), cosf(), tanf(), asinf(), acosf(), atanf(), and
     atan2f() can be used in ANSI mode only.

SEE ALSO
     isnan(3C), matherr(3M), math(5).






































Page 2                       Reliant UNIX 5.44                Printed 11/98