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FLOOR(3)                   Linux Programmer's Manual                  FLOOR(3)



NAME
       floor,  floorf,  floorl - largest integral value not greater than argu-
       ment

SYNOPSIS
       #include <&lt;math.h>&gt;

       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.1-2001  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 error-handling 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 IEEE-754 standard 32-bit and 64-bit 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  man-pages  project.   A
       description  of  the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.



                                  2001-05-31                          FLOOR(3)