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diff --git a/man3/hypot.3 b/man3/hypot.3 new file mode 100644 index 0000000..5f106c6 --- /dev/null +++ b/man3/hypot.3 @@ -0,0 +1,156 @@ +'\" t +.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.\" References consulted: +.\" Linux libc source code +.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) +.\" 386BSD man pages +.\" Modified 1993-07-24 by Rik Faith (faith@cs.unc.edu) +.\" Modified 2002-07-27 by Walter Harms +.\" (walter.harms@informatik.uni-oldenburg.de) +.\" +.TH hypot 3 2023-07-20 "Linux man-pages 6.05.01" +.SH NAME +hypot, hypotf, hypotl \- Euclidean distance function +.SH LIBRARY +Math library +.RI ( libm ", " \-lm ) +.SH SYNOPSIS +.nf +.B #include <math.h> +.PP +.BI "double hypot(double " x ", double " y ); +.BI "float hypotf(float " x ", float " y ); +.BI "long double hypotl(long double " x ", long double " y ); +.fi +.PP +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.PP +.BR hypot (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L + || _XOPEN_SOURCE + || /* Since glibc 2.19: */ _DEFAULT_SOURCE + || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE +.fi +.PP +.BR hypotf (), +.BR hypotl (): +.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 +.RI sqrt( x * x + y * y ). +This is the length of the hypotenuse of a right-angled triangle +with sides of length +.I x +and +.IR y , +or the distance of the point +.RI ( x , y ) +from the origin. +.PP +The calculation is performed without undue overflow or underflow +during the intermediate steps of the calculation. +.\" e.g., hypot(DBL_MIN, DBL_MIN) does the right thing, as does, say +.\" hypot(DBL_MAX/2.0, DBL_MAX/2.0). +.SH RETURN VALUE +On success, these functions return the length of the hypotenuse of +a right-angled triangle +with sides of length +.I x +and +.IR y . +.PP +If +.I x +or +.I y +is an infinity, +positive infinity is returned. +.PP +If +.I x +or +.I y +is a NaN, +and the other argument is not an infinity, +a NaN is returned. +.PP +If the result overflows, +a range error occurs, +and the functions return +.BR HUGE_VAL , +.BR HUGE_VALF , +or +.BR HUGE_VALL , +respectively. +.PP +If both arguments are subnormal, and the result is subnormal, +.\" Actually, could the result not be subnormal if both arguments +.\" are subnormal? I think not -- mtk, Jul 2008 +a range error occurs, +and the correct result is returned. +.SH ERRORS +See +.BR math_error (7) +for information on how to determine whether an error has occurred +when calling these functions. +.PP +The following errors can occur: +.TP +Range error: result overflow +.I errno +is set to +.BR ERANGE . +An overflow floating-point exception +.RB ( FE_OVERFLOW ) +is raised. +.TP +Range error: result underflow +An underflow floating-point exception +.RB ( FE_UNDERFLOW ) +is raised. +.IP +These functions do not set +.I errno +for this case. +.\" This is intentional; see +.\" https://www.sourceware.org/bugzilla/show_bug.cgi?id=6795 +.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 hypot (), +.BR hypotf (), +.BR hypotl () +T} Thread safety MT-Safe +.TE +.sp 1 +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +C99, POSIX.1-2001. +.PP +The variant returning +.I double +also conforms to +SVr4, 4.3BSD. +.SH SEE ALSO +.BR cabs (3), +.BR sqrt (3) |