NAME    [Toc]    [Back]

       ceil, ceilf, ceill - ceiling function: smallest integral value not less
       than argument

SYNOPSIS    [Toc]    [Back]

       #include <math.h>

       double ceil(double x);
       float ceilf(float x);
       long double ceill(long double x);

DESCRIPTION    [Toc]    [Back]

       These functions round x up to the nearest integer.

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 SUSv2 and Austin draft contain 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]

       The  ceil() function conforms to SVID 3, POSIX, BSD 4.3, ISO 9899.  The
       other functions are from C99.

SEE ALSO    [Toc]    [Back]

       floor(3), lrint(3), nearbyint(3), rint(3), round(3), trunc(3)



				  2001-05-31			       CEIL(3)