NAME    [Toc]    [Back]

       round, roundf, roundl - round to nearest integer, away from zero

SYNOPSIS    [Toc]    [Back]

       #include <math.h>

       double round(double x);
       float roundf(float x);
       long double roundl(long double x);

DESCRIPTION    [Toc]    [Back]

       These functions round x to the nearest integer, but round halfway cases
       away from zero (regardless of the current rounding direction),  instead
       of to the nearest even integer like rint().

RETURN VALUE    [Toc]    [Back]

       The  rounded  integer  value. If x is integral or infinite, x itself is
       returned.

ERRORS    [Toc]    [Back]

       No errors other than EDOM and ERANGE can occur.	If x is NaN, then  NaN
       is returned and errno may be set to EDOM.

NOTES    [Toc]    [Back]

       The Austin draft contains text about overflow (which might set errno to
       ERANGE, or raise an exception).	In practice, the result  cannot  overflow
  on any current machine, so this error-handling stuff is just nonsense.
  (More precisely, overflow can  happen  only  when  the  maximum
       value of the exponent is smaller than the number of mantissa bits.  For
       the IEEE-754 standard 32-bit and 64-bit floating point numbers the maximum
  value of the exponent is 128 (resp. 1024), and the number of mantissa
 bits is 24 (resp. 53).)

CONFORMING TO    [Toc]    [Back]

       C99.

SEE ALSO    [Toc]    [Back]

       ceil(3), floor(3), lround(3), nearbyint(3), rint(3), trunc(3)



				  2001-05-31			      ROUND(3)