GENWiki

Premier IT Outsourcing and Support Services within the UK

User Tools

Site Tools


man:floorl

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.
 Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
     floorf(), floorl():
         _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
             || /* Since glibc 2.19: */ _DEFAULT_SOURCE
             || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION

     These functions return the largest integral value that is  not  greater
     than x.
     For example, floor(0.5) is 0.0, and floor(-0.5) is -1.0.

RETURN VALUE

     These functions return the floor of x.
     If x is integral, +0, -0, NaN, or an infinity, x itself is returned.

ERRORS

     No  errors  occur.  POSIX.1-2001 documents a range error for overflows,
     but see NOTES.

ATTRIBUTES

     For  an  explanation  of  the  terms  used   in   this   section,   see
     attributes(7).
     allbox;  lbw27  lb  lb  l  l  l.  Interface Attribute Value T{ floor(),
     floorf(), floorl() T}   Thread safety  MT-Safe

CONFORMING TO

     C99, POSIX.1-2001, POSIX.1-2008.
     The variant returning double also conforms to SVr4, 4.3BSD, C89.

NOTES

     SUSv2 and POSIX.1-2001 contain text about  overflow  (which  might  set
     errno  to ERANGE, or raise an FE_OVERFLOW 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  man-
     tissa 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 number 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 4.16 of the Linux man-pages project.  A
     description of the project, information about reporting bugs,  and  the
     latest     version     of     this    page,    can    be    found    at
     https://www.kernel.org/doc/man-pages/.
                                2017-09-15                          FLOOR(3)
/data/webs/external/dokuwiki/data/pages/man/floorl.txt · Last modified: 2019/05/17 09:47 by 127.0.0.1

Was this page helpful?-10+1

Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki