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diff --git a/man3/fpclassify.3 b/man3/fpclassify.3 deleted file mode 100644 index 8e72dd3..0000000 --- a/man3/fpclassify.3 +++ /dev/null @@ -1,145 +0,0 @@ -'\" t -.\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de) -.\" -.\" SPDX-License-Identifier: GPL-1.0-or-later -.\" -.\" This was done with the help of the glibc manual. -.\" -.\" 2004-10-31, aeb, corrected -.TH fpclassify 3 2023-10-31 "Linux man-pages 6.7" -.SH NAME -fpclassify, isfinite, isnormal, isnan, isinf \- floating-point -classification macros -.SH LIBRARY -Math library -.RI ( libm ", " \-lm ) -.SH SYNOPSIS -.nf -.B #include <math.h> -.P -.BI "int fpclassify(" x ); -.BI "int isfinite(" x ); -.BI "int isnormal(" x ); -.BI "int isnan(" x ); -.BI "int isinf(" x ); -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.\" I haven't fully grokked the source to determine the FTM requirements; -.\" in part, the following has been tested by experiment. -.BR fpclassify (), -.BR isfinite (), -.BR isnormal (): -.nf - _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L -.fi -.P -.BR isnan (): -.nf - _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L - || _XOPEN_SOURCE - || /* Since glibc 2.19: */ _DEFAULT_SOURCE - || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE -.fi -.P -.BR isinf (): -.nf - _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L - || /* Since glibc 2.19: */ _DEFAULT_SOURCE - || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE -.fi -.SH DESCRIPTION -Floating point numbers can have special values, such as -infinite or NaN. -With the macro -.BI fpclassify( x ) -you can find out what type -.I x -is. -The macro takes any floating-point expression as argument. -The result is one of the following values: -.TP 14 -.B FP_NAN -.I x -is "Not a Number". -.TP -.B FP_INFINITE -.I x -is either positive infinity or negative infinity. -.TP -.B FP_ZERO -.I x -is zero. -.TP -.B FP_SUBNORMAL -.I x -is too small to be represented in normalized format. -.TP -.B FP_NORMAL -if nothing of the above is correct then it must be a -normal floating-point number. -.P -The other macros provide a short answer to some standard questions. -.TP 14 -.BI isfinite( x ) -returns a nonzero value if -.br -(fpclassify(x) != FP_NAN && fpclassify(x) != FP_INFINITE) -.TP -.BI isnormal( x ) -returns a nonzero value if -(fpclassify(x) == FP_NORMAL) -.TP -.BI isnan( x ) -returns a nonzero value if -(fpclassify(x) == FP_NAN) -.TP -.BI isinf( x ) -returns 1 if -.I x -is positive infinity, and \-1 if -.I x -is negative infinity. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR fpclassify (), -.BR isfinite (), -.BR isnormal (), -.BR isnan (), -.BR isinf () -T} Thread safety MT-Safe -.TE -.SH STANDARDS -C11, POSIX.1-2008. -.SH HISTORY -POSIX.1-2001, C99. -.P -In glibc 2.01 and earlier, -.BR isinf () -returns a nonzero value (actually: 1) if -.I x -is positive infinity or negative infinity. -(This is all that C99 requires.) -.SH NOTES -For -.BR isinf (), -the standards merely say that the return value is nonzero -if and only if the argument has an infinite value. -.SH SEE ALSO -.BR finite (3), -.BR INFINITY (3), -.BR isgreater (3), -.BR signbit (3) |