ceil, ceilf, ceill — ceiling function: smallest integral value not less than argument
#include <math.h>
double ceil( |
double | x) ; |
float
ceilf( |
float | x) ; |
long
double ceill( |
long double | x) ; |
![]() |
Note |
---|---|
Link with −lm. |
No errors other than EDOM and ERANGE can occur. If
x
is NaN, then NaN is
returned and errno
may be set to
EDOM.
SUSv2 and POSIX.1-2001 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).)
The ceil
() function conforms
to SVr4, POSIX.1-2001, 4.3BSD, C89, C99. The other functions
are from C99.
floor(3), lrint(3), nearbyint(3), rint(3), round(3), trunc(3)
|