significand(3) — Linux manual page

significand(3)           Library Functions Manual          significand(3)

NAME         top

       significand, significandf, significandl - get mantissa of
       floating-point number

LIBRARY         top

       Math library (libm, -lm)

SYNOPSIS         top

       #include <math.h>

       double significand(double x);
       float significandf(float x);
       long double significandl(long double x);

   Feature Test Macro Requirements for glibc (see
   feature_test_macros(7)):

       significand(), significandf(), significandl():
           /* Since glibc 2.19: */ _DEFAULT_SOURCE
               || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION         top

       These functions return the mantissa of x scaled to the range
       [1, FLT_RADIX).  They are equivalent to

           scalb(x, (double) -ilogb(x))

       This function exists mainly for use in certain standardized tests
       for IEEE 754 conformance.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ significand(), significandf(),       │ Thread safety │ MT-Safe │
       │ significandl()                       │               │         │
       └──────────────────────────────────────┴───────────────┴─────────┘

STANDARDS         top

       None.

       significand()
              BSD.

HISTORY         top

       significand()
              BSD.

SEE ALSO         top

       ilogb(3), scalb(3)

COLOPHON         top

       This page is part of the man-pages (Linux kernel and C library
       user-space interface documentation) project.  Information about
       the project can be found at 
       ⟨https://www.kernel.org/doc/man-pages/⟩.  If you have a bug report
       for this manual page, see
       ⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩.
       This page was obtained from the tarball man-pages-6.15.tar.gz
       fetched from
       ⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on
       2025-08-11.  If you discover any rendering problems in this HTML
       version of the page, or you believe there is a better or more up-
       to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not
       part of the original manual page), send a mail to
       man-pages@man7.org

Linux man-pages 6.15            2025-05-17                 significand(3)

Pages that refer to this page: ilogb(3)

HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH.