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man:isinff

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

NAME

     finite,  finitef, finitel, isinf, isinff, isinfl, isnan, isnanf, isnanl
     - BSD floating-point classification functions

SYNOPSIS

     #include <math.h>
     int finite(double x);
     int finitef(float x);
     int finitel(long double x);
     int isinf(double x);
     int isinff(float x);
     int isinfl(long double x);
     int isnan(double x);
     int isnanf(float x);
     int isnanl(long double x);
 Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
     finite(), finitef(), finitel():
         /* Glibc since 2.19: */ _DEFAULT_SOURCE
             || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
     isinf():
         _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE
             || /* Glibc since 2.19: */ _DEFAULT_SOURCE
             || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
     isinff(), isinfl():
         /* Glibc since 2.19: */ _DEFAULT_SOURCE
             || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
     isnan():
         _XOPEN_SOURCE || _ISOC99_SOURCE
             || /* Glibc since 2.19: */ _DEFAULT_SOURCE
             || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
     isnanf(), isnanl():
         _XOPEN_SOURCE >= 600
             || /* Glibc since 2.19: */ _DEFAULT_SOURCE
             || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION

     The finite(), finitef(), and finitel() functions return a nonzero value
     if x is neither infinite nor a "not-a-number" (NaN) value, and 0 other-
     wise.
     The isnan(), isnanf(), and isnanl() functions return a nonzero value if
     x is a NaN value, and 0 otherwise.
     The isinf(), isinff(), and isinfl() functions return 1 if x is positive
     infinity, -1 if x is negative infinity, and 0 otherwise.

ATTRIBUTES

     For  an  explanation  of  the  terms  used   in   this   section,   see
     attributes(7).
     allbox;  lbw31  lb  lb  l  l l.  Interface Attribute Value T{ finite(),
     finitef(), finitel(),
     isinf(), isinff(), isinfl(),
     isnan(), isnanf(), isnanl() T}   Thread safety  MT-Safe

NOTES

     Note that these functions are obsolete.  C99 defines macros isfinite(),
     isinf(), and isnan() (for all types) replacing them.  Further note that
     the C99 isinf() has weaker guarantees on the return value.  See fpclas-
     sify(3).

SEE ALSO

     fpclassify(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                         FINITE(3)
/data/webs/external/dokuwiki/data/pages/man/isinff.txt · Last modified: 2019/05/17 09:32 by 127.0.0.1

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