Originální popis anglicky:
j0, j1, jn - Bessel functions of the first kind
Návod, kniha: POSIX Programmer's Manual
#include <math.h>
double j0(double
x);
double j1(double
x);
double jn(int
n, double x);
The
j0(),
j1(), and
jn() functions shall compute Bessel
functions of
x of the first 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.
Upon successful completion, these functions shall return the relevant Bessel
value of
x of the first kind.
If the
x argument is too large in magnitude, or the correct result would
cause underflow, 0 shall be returned and a range error may occur.
If
x is NaN, a NaN shall be returned.
These functions may fail if:
- Range Error
- The value of x was too large in magnitude, or an
underflow occurred.
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.
No other errors shall occur.
The following sections are informative.
None.
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.
None.
None.
feclearexcept() ,
fetestexcept() ,
isnan() ,
y0() ,
the Base Definitions volume of IEEE Std 1003.1-2001, Section
4.18, Treatment of Error Conditions for Mathematical Functions,
<math.h>
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
.
