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diff --git a/upstream/archlinux/man3p/log1p.3p b/upstream/archlinux/man3p/log1p.3p new file mode 100644 index 00000000..e892c67e --- /dev/null +++ b/upstream/archlinux/man3p/log1p.3p @@ -0,0 +1,179 @@ +'\" et +.TH LOG1P "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.\" +.SH NAME +log1p, +log1pf, +log1pl +\(em compute a natural logarithm +.SH SYNOPSIS +.LP +.nf +#include <math.h> +.P +double log1p(double \fIx\fP); +float log1pf(float \fIx\fP); +long double log1pl(long double \fIx\fP); +.fi +.SH DESCRIPTION +The functionality described on this reference page is aligned with the +ISO\ C standard. Any conflict between the requirements described here and the +ISO\ C standard is unintentional. This volume of POSIX.1\(hy2017 defers to the ISO\ C standard. +.P +These functions shall compute log\d\s-3e\s+3\u(1.0 + \fIx\fP). +.P +An application wishing to check for error situations should set +.IR errno +to zero and call +.IR feclearexcept (FE_ALL_EXCEPT) +before calling these functions. On return, if +.IR errno +is non-zero or \fIfetestexcept\fR(FE_INVALID | FE_DIVBYZERO | +FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error has occurred. +.SH "RETURN VALUE" +Upon successful completion, these functions shall return the natural +logarithm of 1.0 + +.IR x . +.P +If +.IR x +is \-1, a pole error shall occur and +\fIlog1p\fR(), +\fIlog1pf\fR(), +and +\fIlog1pl\fR() +shall return \-HUGE_VAL, \-HUGE_VALF, and \-HUGE_VALL, +respectively. +.P +For finite values of +.IR x +that are less than \-1, +or if +.IR x +is \-Inf, +a domain error shall occur, and +either a NaN (if supported), or +an implementation-defined value shall be returned. +.P +If +.IR x +is NaN, a NaN shall be returned. +.P +If +.IR x +is \(+-0, or +Inf, +.IR x +shall be returned. +.P +If +.IR x +is subnormal, a range error may occur +.br +and +.IR x +should be returned. +.P +If +.IR x +is not returned, +\fIlog1p\fR(), +\fIlog1pf\fR(), +and +\fIlog1pl\fR() +shall return an implementation-defined value no greater in magnitude +than DBL_MIN, FLT_MIN, and LDBL_MIN, respectively. +.SH ERRORS +These functions shall fail if: +.IP "Domain\ Error" 12 +The finite value of +.IR x +is less than \-1, +or +.IR x +is \-Inf. +.RS 12 +.P +If the integer expression (\fImath_errhandling\fR & MATH_ERRNO) is +non-zero, then +.IR errno +shall be set to +.BR [EDOM] . +If the integer expression (\fImath_errhandling\fR & MATH_ERREXCEPT) is +non-zero, then the invalid floating-point exception shall be raised. +.RE +.IP "Pole\ Error" 12 +The value of +.IR x +is \-1. +.RS 12 +.P +If the integer expression (\fImath_errhandling\fR & MATH_ERRNO) is +non-zero, then +.IR errno +shall be set to +.BR [ERANGE] . +If the integer expression (\fImath_errhandling\fR & MATH_ERREXCEPT) is +non-zero, then the divide-by-zero floating-point exception shall be +raised. +.RE +.br +.P +These functions may fail if: +.IP "Range\ Error" 12 +The value of +.IR x +is subnormal. +.RS 12 +.P +If the integer expression (\fImath_errhandling\fR & MATH_ERRNO) is +non-zero, then +.IR errno +shall be set to +.BR [ERANGE] . +If the integer expression (\fImath_errhandling\fR & MATH_ERREXCEPT) is +non-zero, then the underflow floating-point exception shall be raised. +.RE +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +On error, the expressions (\fImath_errhandling\fR & MATH_ERRNO) and +(\fImath_errhandling\fR & MATH_ERREXCEPT) are independent of each +other, but at least one of them must be non-zero. +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIfeclearexcept\fR\^(\|)", +.IR "\fIfetestexcept\fR\^(\|)", +.IR "\fIlog\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "Section 4.20" ", " "Treatment of Error Conditions for Mathematical Functions", +.IR "\fB<math.h>\fP" +.\" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +In the event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . +.PP +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |