nan, nanf, nanl - return 'Not a Number'


   #include <math.h>

   double nan(const char *tagp);
   float nanf(const char *tagp);
   long double nanl(const char *tagp);

   Link with -lm.

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

   nan(), nanf(), nanl():
       _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L


   These functions return a representation (determined by tagp) of a quiet
   NaN.   If  the  implementation  does  not  support  quiet  NaNs,  these
   functions return zero.

   The call nan("char-sequence") is equivalent to:

       strtod("NAN(char-sequence)", NULL);

   Similarly, calls to nanf() and nanl() are equivalent to analogous calls
   to strtof(3) and strtold(3).

   The argument tagp is used  in  an  unspecified  manner.   On  IEEE  754
   systems,  there  are many representations of NaN, and tagp selects one.
   On other systems it may do nothing.


   These functions first appeared in glibc in version 2.1.


   For  an  explanation  of  the  terms  used   in   this   section,   see

   │InterfaceAttributeValue          │
   │nan(), nanf(), nanl() │ Thread safety │ MT-Safe locale │


   C99,  POSIX.1-2001,  POSIX.1-2008.   See  also IEC 559 and the appendix
   with recommended functions in IEEE 754/IEEE 854.


   isnan(3), strtod(3), math_error(7)


   This page is part of release 4.09 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

More Linux Commands

XGetFontProperty(3) - load or unload fonts and font metric s
The XLoadFont function loads the specified font and returns its associated font ID. If the font name is not in the Host Portable Character Encoding, the result

glEdgeFlagPointer(3gl) - define an array of edge flags......
glEdgeFlagPointer specifies the location and data of an array of boolean edge flags to use when rendering. stride specifies the byte stride from one edge flag t

control.ctl(5) - Specify handling of Usenet control messages
The file pathetc/control.ctl is used to determine what action is taken when a control message is received. It is read by controlchan, which is normally invoked

XDGACopyArea(3) - Client library for the XFree86-DGA extensi
The XFree86-DGA extension is an X server extension for allowing client programs direct access to the video frame buffer. This is a brief description of the prog

pkg_mkIndex(n) - Build an index for automatic loading of pac
Pkg_mkIndex is a utility procedure that is part of the standard Tcl library. It is used to create index files that allow packages to be loaded automatically whe

ggz.h(3) - (unknown subject) (Library - Linux man page).....
Author: Brent M. Hendricks Date: Fri Nov 2 23:32:17 2001 Id.RS 4 ggz.h,v 1.59 2005/05/21 10:19:22 josef Exp Header file for ggz components lib Copyright (C) 200

noqiflush_sp(3ncurses) - curses screen-pointer extension....
This implementation can be configured to provide a set of functions which improve the ability to manage multiple screens. This feature can be added to any of th

inews(1) - Post a Usenet article to the local news server...
inews reads a Usenet news article, perhaps with headers, from file or standard input if no file is given. It adds some headers and performs some consistency che

blogger(8) - writes messages to a running blogd process.....
blogger is used to send messages to the blogd process during boot phase. These messages will only appear in the boot logging file /var/log/boot.msg and not on /

lsattr(1) - list file attributes on a Linux second extended
lsattr lists the file attributes on a second extended file system. See chattr(1) for a description of the attributes and what they mean. OPTIONS -R Recursively

gnutls_priority_init(3) - API function - Linux manual page
Sets priorities for the ciphers, key exchange methods, macs and compression methods. The priorities option allows you to specify a colon separated list of the c

XtIsRealized(3) - realize and unrealize widgets (Man Page)
If the widget is already realized, XtRealizeWidget simply returns. Otherwise, it performs the following: * Binds all action names in the widgets translation tab

We can't live, work or learn in freedom unless the software we use is free.