NAME

j0, j1, jn, y0, y1, yn − Bessel functions

SYNOPSIS

#include <math.h>

double j0 (x)
double x;

double j1 (x)
double x;

double jn (n, x)
int n;
double x;

double y0 (x)
double x;

double y1 (x)
double x;

double yn (n, x)
int n;
double x;

DESCRIPTION

J0 and j1 return Bessel functions of x of the first kind of orders 0 and 1 respectively.  Jn returns the Bessel function of x of the first kind of order n.

Y0 and y1 return the Bessel functions of x of the second kind of orders 0 and 1 respectively.  Yn returns the Bessel function of x of the second kind of order n. The value of x must be positive. 

ERRORS

Series 300
Non-positive arguments cause y0, y1 and yn to return the value −HUGE_VAL and to set errno to EDOM.  They also cause a message indicating DOMAIN error to be printed on the standard error output.  Arguments too large in magnitude cause j0, j1, jn, y0, y1 , and yn to return 0.0 and set errno to ERANGE.  In addition, a message indicating TLOSS error is printed on the standard error output. 

Series 800 (/lib/libm.a)
Non-positive arguments cause y0, y1 , and yn to return the value −HUGE_VAL and to set errno to EDOM.  They also cause a message indicating DOMAIN error to be printed on the standard error output. 

Arguments too large in magnitude cause j0, j1, jn, y0, y1 , and yn to return 0.0 and set errno to ERANGE.  In addition, a message indicating TLOSS error is printed on the standard error output. 

j0, j1, jn, y0, y1 , and yn return NaN and set errno to EDOM when x is NaN or ±INFINITY .  In addition, a message indicating DOMAIN error is printed on the standard error output. 

Series 800 (ANSI C /lib/libM.a)
No error messages are printed on the standard error output.

Non-positive arguments cause y0, y1 , and yn to return the value NaN and to set errno to EDOM.  IP Arguments too large in magnitude cause j0, j1, jn, y0, y1 , and yn to return 0.0 and set errno to ERANGE. 

j0, j1, jn, y0, y1 , and yn return NaN and set errno to EDOM when x is NaN or ±INFINITY . 

These error-handling procedures can be changed with the function matherr(3M).

SEE ALSO

isinf(3M), isnan(3M), matherr(3M). 

STANDARDS CONFORMANCE

j0: SVID2, XPG2, XPG3

j1: SVID2, XPG2, XPG3

jn: SVID2, XPG2, XPG3

y0: SVID2, XPG2, XPG3

y1: SVID2, XPG2, XPG3

yn: SVID2, XPG2, XPG3

Hewlett-Packard Company  —  HP-UX Release 7.0: Sept 1989