From 3d08cd331c1adcf0d917392f7e527b3f00511748 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 24 May 2024 06:52:22 +0200 Subject: Merging upstream version 6.8. Signed-off-by: Daniel Baumann --- man/man3/erfc.3 | 134 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 134 insertions(+) create mode 100644 man/man3/erfc.3 (limited to 'man/man3/erfc.3') diff --git a/man/man3/erfc.3 b/man/man3/erfc.3 new file mode 100644 index 0000000..70bdd7a --- /dev/null +++ b/man/man3/erfc.3 @@ -0,0 +1,134 @@ +'\" t +.\" Copyright 2008, Linux Foundation, written by Michael Kerrisk +.\" +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.TH erfc 3 2024-05-02 "Linux man-pages (unreleased)" +.SH NAME +erfc, erfcf, erfcl \- complementary error function +.SH LIBRARY +Math library +.RI ( libm ", " \-lm ) +.SH SYNOPSIS +.nf +.B #include +.P +.BI "double erfc(double " x ); +.BI "float erfcf(float " x ); +.BI "long double erfcl(long double " x ); +.fi +.P +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.P +.BR erfc (): +.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 erfcf (), +.BR erfcl (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L + || /* Since glibc 2.19: */ _DEFAULT_SOURCE + || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE +.fi +.SH DESCRIPTION +These functions return the complementary error function of +.IR x , +that is, 1.0 \- erf(x). +.SH RETURN VALUE +On success, these functions return the complementary error function of +.IR x , +a value in the range [0,2]. +.P +If +.I x +is a NaN, a NaN is returned. +.P +If +.I x +is +0 or \-0, 1 is returned. +.P +If +.I x +is positive infinity, ++0 is returned. +.P +If +.I x +is negative infinity, ++2 is returned. +.P +If the function result underflows and produces an unrepresentable value, +the return value is 0.0. +.P +If the function result underflows but produces a representable +(i.e., subnormal) value, +.\" e.g., erfc(27) on x86-32 +that value is returned, and +a range error occurs. +.SH ERRORS +See +.BR math_error (7) +for information on how to determine whether an error has occurred +when calling these functions. +.P +The following errors can occur: +.TP +Range error: result underflow (result is subnormal) +.\" .I errno +.\" is set to +.\" .BR ERANGE . +An underflow floating-point exception +.RB ( FE_UNDERFLOW ) +is raised. +.P +These functions do not set +.IR errno . +.\" It is intentional that these functions do not set errno for this case +.\" see https://www.sourceware.org/bugzilla/show_bug.cgi?id=6785 +.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 erfc (), +.BR erfcf (), +.BR erfcl () +T} Thread safety MT-Safe +.TE +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +C99, POSIX.1-2001. +.P +The variant returning +.I double +also conforms to +SVr4, 4.3BSD. +.SH NOTES +The +.BR erfc (), +.BR erfcf (), +and +.BR erfcl () +functions are provided to avoid the loss accuracy that +would occur for the calculation 1-erf(x) for large values of +.I x +(for which the value of erf(x) approaches 1). +.SH SEE ALSO +.BR cerf (3), +.BR erf (3), +.BR exp (3) -- cgit v1.2.3