FLOOR(3) Linux Programmer's Manual FLOOR(3)
NAME
floor, floorf, floorl  largest integral value not greater than argu
ment
SYNOPSIS
#include <<math.h>>
double floor(double x);
float floorf(float x);
long double floorl(long double x);
Link with lm.
DESCRIPTION
These functions round x down to the nearest integer.
RETURN VALUE
The rounded integer value. If x is integral or infinite, x itself is
returned.
ERRORS
No errors other than EDOM and ERANGE can occur. If x is NaN, then NaN
is returned and errno may be set to EDOM.
CONFORMING TO
The floor() function conforms to SVr4, 4.3BSD, C89. The other func
tions are from C99.
NOTES
SUSv2 and POSIX.12001 contain text about overflow (which might set
errno to ERANGE, or raise an exception). In practice, the result can
not overflow on any current machine, so this errorhandling stuff is
just nonsense. (More precisely, overflow can happen only when the max
imum value of the exponent is smaller than the number of mantissa bits.
For the IEEE754 standard 32bit and 64bit floating point numbers the
maximum value of the exponent is 128 (respectively, 1024), and the num
ber of mantissa bits is 24 (respectively, 53).)
SEE ALSO
ceil(3), lrint(3), nearbyint(3), rint(3), round(3), trunc(3)
COLOPHON
This page is part of release 3.05 of the Linux manpages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/manpages/.
20010531 FLOOR(3)
