INFINITY(3)                                           Library Functions Manual                                          INFINITY(3)

NAME
       INFINITY, NAN, HUGE_VAL, HUGE_VALF, HUGE_VALL - floating-point constants

LIBRARY
       Math library (libm)

SYNOPSIS
       #define _ISOC99_SOURCE      /* See feature_test_macros(7) */
       #include <math.h>

       INFINITY

       NAN

       HUGE_VAL
       HUGE_VALF
       HUGE_VALL

DESCRIPTION
       The macro INFINITY expands to a float constant representing positive infinity.

       The  macro NAN expands to a float constant representing a quiet NaN (when supported).  A quiet NaN is a NaN ("not-a-number")
       that does not raise exceptions when it is used in arithmetic.  The opposite is a signaling NaN.  See IEC 60559:1989.

       The macros HUGE_VAL, HUGE_VALF, HUGE_VALL expand to constants of types double, float, and long  double,  respectively,  that
       represent a large positive value, possibly positive infinity.

STANDARDS
       C99.

       On  a  glibc  system, the macro HUGE_VAL is always available.  Availability of the NAN macro can be tested using #ifdef NAN,
       and similarly for INFINITY, HUGE_VALF, HUGE_VALL.  They will be defined by <math.h> if _ISOC99_SOURCE or _GNU_SOURCE is  de‐
       fined, or __STDC_VERSION__ is defined and has a value not less than 199901L.

SEE ALSO
       fpclassify(3), math_error(7)

Linux man-pages 6.03                                         2022-10-09                                                 INFINITY(3)