Compute a Bessel function of the second kind of a given order
#include <math.h>
double yn( int n,
double x );
float ynf( int n,
float x );
These functions compute the Bessel function for x of the second kind of order n.
To check for error situations, use feclearexcept() and fetestexcept(). For example:
The result of the Bessel function for x of the second kind of order n.
| If x is: | These functions return: | Errors: |
|---|---|---|
| Negative, including -Inf | NaN | FE_INVALID |
| 0.0 | -Inf | FE_DIVBYZERO |
| NaN | NaN | — |
| Inf | 0.0 | — |
| If the correct result would cause: | These functions return: | Errors: |
|---|---|---|
| Overflow | -Inf | FE_OVERFLOW |
| Underflow | 0.0 |
These functions raise FE_INEXACT if the FPU reports that the result can't be exactly represented as a floating-point number.
yn() is POSIX 1003.1 XSI; ynf() is Unix
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | No |
| Signal handler | No |
| Thread | Yes |