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diff --git a/man-pages-posix-2003/man3p/log1p.3p b/man-pages-posix-2003/man3p/log1p.3p new file mode 100644 index 0000000..76f4e48 --- /dev/null +++ b/man-pages-posix-2003/man3p/log1p.3p @@ -0,0 +1,117 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "LOG1P" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" log1p +.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 \- compute a natural logarithm +.SH SYNOPSIS +.LP +\fB#include <math.h> +.br +.sp +double log1p(double\fP \fIx\fP\fB); +.br +float log1pf(float\fP \fIx\fP\fB); +.br +long double log1pl(long double\fP \fIx\fP\fB); +.br +\fP +.SH DESCRIPTION +.LP +These functions shall compute log_e(1.0 + \fIx\fP). +.LP +An application wishing to check for error situations should set \fIerrno\fP +to zero and call +\fIfeclearexcept\fP(FE_ALL_EXCEPT) before calling these functions. +On return, if \fIerrno\fP is non-zero or +\fIfetestexcept\fP(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) +is non-zero, an error has occurred. +.SH RETURN VALUE +.LP +Upon successful completion, these functions shall return the natural +logarithm of 1.0 + \fIx\fP. +.LP +If \fIx\fP is -1, a pole error shall occur and \fIlog1p\fP(), \fIlog1pf\fP(), +and \fIlog1pl\fP() shall return -HUGE_VAL, +-HUGE_VALF, and -HUGE_VALL, respectively. +.LP +For finite values of \fIx\fP that are less than -1, or if \fIx\fP +is -Inf, a domain error shall occur, and either a NaN (if supported), +or an implementation-defined value shall be returned. +.LP +If +\fIx\fP is NaN, a NaN shall be returned. +.LP +If \fIx\fP is \(+-0, or +Inf, \fIx\fP shall be returned. +.LP +If \fIx\fP is subnormal, a range error may occur and \fIx\fP should +be returned. +.SH ERRORS +.LP +These functions shall fail if: +.TP 7 +Domain\ Error +The finite value of \fIx\fP is less than -1, or \fIx\fP is -Inf. +.LP +If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, +then \fIerrno\fP shall be set to [EDOM]. If the +integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, +then the invalid floating-point exception shall be +raised. +.TP 7 +Pole\ Error +The value of \fIx\fP is -1. +.LP +If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, +then \fIerrno\fP shall be set to [ERANGE]. If the +integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, +then the divide-by-zero floating-point exception shall be +raised. +.sp +.LP +These functions may fail if: +.TP 7 +Range\ Error +The value of \fIx\fP is subnormal. +.LP +If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, +then \fIerrno\fP shall be set to [ERANGE]. If the +integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, +then the underflow floating-point exception shall be +raised. +.sp +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +On error, the expressions (math_errhandling & MATH_ERRNO) and (math_errhandling +& MATH_ERREXCEPT) are independent of +each other, but at least one of them must be non-zero. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIfeclearexcept\fP(), \fIfetestexcept\fP(), \fIlog\fP(), the Base +Definitions volume of IEEE\ Std\ 1003.1-2001, Section 4.18, Treatment +of Error Conditions for Mathematical Functions, \fI<math.h>\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 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 . |