Updated: 2021/Apr/14

J0(3) Library Functions Manual J0(3)NAMEj0,j0f,j1,j1f,jn,jnf,y0,y0f,y1,y1f,yn,ynf- Bessel functions of first and second kindLIBRARYMath Library (libm, -lm)SYNOPSIS#include<math.h>doublej0(double x); floatj0f(float x); doublej1(double x); floatj1f(float x); doublejn(int n, double x); floatjnf(int n, float x); doubley0(double x); floaty0f(float x); doubley1(double x); floaty1f(float x); doubleyn(int n, double x); floatynf(int n, float x);DESCRIPTIONThe functionsj0(),j0f(),j1() andj1f() compute the Bessel function of the first kind of the order 0 and the order 1, respectively, for the real value x; the functionsjn() andjnf() compute the Bessel function of the first kind of the integer order n for the real value x. The functionsy0(),y0f(),y1() andy1f() compute the linearly independent Bessel function of the second kind of the order 0 and the order 1, respectively, for the positive integer value x (expressed as a double); the functionsyn() andynf() compute the Bessel function of the second kind for the integer order n for the positive integer value x (expressed as a double).RETURNVALUESIf these functions are successful, the computed value is returned, otherwise the global variable errno is set to EDOM and a reserve operand fault is generated.SEEALSOmath(3)HISTORYThis set of functions appeared in Version 7 AT&T UNIX. NetBSD 9.99 April 19, 1991 NetBSD 9.99