функции Бесселя второго рода (Bessel functions of the second kind)
Пролог (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.
Имя (Name)
y0, y1, yn — Bessel functions of the second kind
Синопсис (Synopsis)
#include <math.h>
double y0(double x);
double y1(double x);
double yn(int n, double x);
Описание (Description)
The y0(), y1(), and yn() functions shall compute Bessel functions
of x of the second kind of orders 0, 1, and n, respectively.
An application wishing to check for error situations should set
errno to zero and call feclearexcept(FE_ALL_EXCEPT) before
calling these functions. On return, if errno is non-zero or
fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW |
FE_UNDERFLOW) is non-zero, an error has occurred.
Возвращаемое значение (Return value)
Upon successful completion, these functions shall return the
relevant Bessel value of x of the second kind.
If x is NaN, NaN shall be returned.
If the x argument to these functions is negative, -HUGE_VAL or
NaN shall be returned, and a domain error may occur.
If x is 0.0, -HUGE_VAL shall be returned and a pole error may
occur.
If the correct result would cause underflow, 0.0 shall be
returned and a range error may occur.
If the correct result would cause overflow, -HUGE_VAL or 0.0
shall be returned and a range error may occur.
Ошибки (Error)
These functions may fail if:
Domain Error
The value of x is negative.
If the integer expression (math_errhandling &
MATH_ERRNO) is non-zero, then errno 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.
Pole Error The value of x is zero.
If the integer expression (math_errhandling &
MATH_ERRNO) is non-zero, then errno 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.
Range Error The correct result would cause overflow.
If the integer expression (math_errhandling &
MATH_ERRNO) is non-zero, then errno 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.
Range Error The value of x is too large in magnitude, or the
correct result would cause underflow.
If the integer expression (math_errhandling &
MATH_ERRNO) is non-zero, then errno 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.
The following sections are informative.
Примеры (Examples)
None.
Использование в приложениях (Application usage)
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.
Обоснование (Rationale)
None.
Будущие направления (Future directions)
None.
Смотри также (See also)
feclearexcept(3p), fetestexcept(3p), isnan(3p), j0(3p)
The Base Definitions volume of POSIX.1‐2017, Section 4.20,
Treatment of Error Conditions for Mathematical Functions,
math.h(0p)
