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diff --git a/upstream/archlinux/man3p/hypot.3p b/upstream/archlinux/man3p/hypot.3p new file mode 100644 index 00000000..095a5721 --- /dev/null +++ b/upstream/archlinux/man3p/hypot.3p @@ -0,0 +1,158 @@ +'\" et +.TH HYPOT "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 +hypot, +hypotf, +hypotl +\(em Euclidean distance function +.SH SYNOPSIS +.LP +.nf +#include <math.h> +.P +double hypot(double \fIx\fP, double \fIy\fP); +float hypotf(float \fIx\fP, float \fIy\fP); +long double hypotl(long double \fIx\fP, long double \fIy\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 the value of the square root of +.IR x \s-3\u2\d\s+3+\c +.IR y \s-3\u2\d\s+3 +without undue overflow or underflow. +.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 length of +the hypotenuse of a right-angled triangle with sides of length +.IR x +and +.IR y . +.P +If the correct value would cause overflow, a range error shall occur +and +\fIhypot\fR(), +\fIhypotf\fR(), +and +\fIhypotl\fR() +shall return the value of the macro HUGE_VAL, HUGE_VALF, and HUGE_VALL, +respectively. +.P +If +.IR x +or +.IR y +is \(+-Inf, +Inf shall be returned (even if one of +.IR x +or +.IR y +is NaN). +.P +If +.IR x +or +.IR y +is NaN, and the other is not \(+-Inf, a NaN shall be returned. +.P +If both arguments are subnormal and the correct result is subnormal, +a range error may occur and the correct result shall be returned. +.SH ERRORS +These functions shall fail if: +.IP "Range\ Error" 12 +The result overflows. +.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 overflow floating-point exception shall be raised. +.RE +.P +These functions may fail if: +.IP "Range\ Error" 12 +The result underflows. +.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 +See the EXAMPLES section in +\fIatan2\fR(). +.SH "APPLICATION USAGE" +\fIhypot\fR(\fIx\fR,\fIy\fR), \fIhypot\fR(\fIy\fR,\fIx\fR), and +\fIhypot\fR(\fIx\fR, \-\fIy\fR) are equivalent. +.P +\fIhypot\fR(\fIx\fR, \(+-0) is equivalent to \fIfabs\fR(\fIx\fR). +.P +Underflow only happens when both +.IR x +and +.IR y +are subnormal and the (inexact) result is also subnormal. +.P +These functions take precautions against overflow during intermediate +steps of the computation. +.P +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 "\fIatan2\fR\^(\|)", +.IR "\fIfeclearexcept\fR\^(\|)", +.IR "\fIfetestexcept\fR\^(\|)", +.IR "\fIisnan\fR\^(\|)", +.IR "\fIsqrt\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 . |