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diff --git a/man-pages-posix-2003/man3p/hypot.3p b/man-pages-posix-2003/man3p/hypot.3p new file mode 100644 index 0000000..a7da3f6 --- /dev/null +++ b/man-pages-posix-2003/man3p/hypot.3p @@ -0,0 +1,122 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "HYPOT" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" hypot +.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 \- Euclidean distance function +.SH SYNOPSIS +.LP +\fB#include <math.h> +.br +.sp +double hypot(double\fP \fIx\fP\fB, double\fP \fIy\fP\fB); +.br +float hypotf(float\fP \fIx\fP\fB, float\fP \fIy\fP\fB); +.br +long double hypotl(long double\fP \fIx\fP\fB, long double\fP \fIy\fP\fB); +.br +\fP +.SH DESCRIPTION +.LP +These functions shall compute the value of the square root of \fIx\fP**2+ +\fIy\fP**2 without undue overflow or underflow. +.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 length +of the hypotenuse of a right-angled triangle with sides of +length \fIx\fP and \fIy\fP. +.LP +If the correct value would cause overflow, a range error shall occur +and \fIhypot\fP(), \fIhypotf\fP(), and \fIhypotl\fP() +shall return the value of the macro HUGE_VAL, HUGE_VALF, and HUGE_VALL, +respectively. +.LP +If +\fIx\fP or \fIy\fP is \(+-Inf, +Inf shall be returned (even if one +of \fIx\fP or \fIy\fP is NaN). +.LP +If \fIx\fP or \fIy\fP is NaN, and the other is not \(+-Inf, a NaN +shall be returned. +.LP +If both arguments are subnormal and the correct result is subnormal, +a range error may occur and the correct result is returned. +.SH ERRORS +.LP +These functions shall fail if: +.TP 7 +Range\ Error +The result overflows. +.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 overflow floating-point exception shall be +raised. +.sp +.LP +These functions may fail if: +.TP 7 +Range\ Error +The result underflows. +.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 +\fIhypot\fP(\fIx\fP,\fIy\fP), \fIhypot\fP(\fIy\fP,\fIx\fP), and \fIhypot\fP(\fIx\fP, +-\fIy\fP) are equivalent. +.LP +\fIhypot\fP(\fIx\fP, \(+-0) is equivalent to \fIfabs\fP(\fIx\fP). +.LP +Underflow only happens when both \fIx\fP and \fIy\fP are subnormal +and the (inexact) result is also subnormal. +.LP +These functions take precautions against overflow during intermediate +steps of the computation. +.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(), \fIisnan\fP(), \fIsqrt\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 . |