J0(3) | Library Functions Manual | J0(3)

# NAME

`j0`, `j0f`, `j1`, `j1f`, `jn`, `jnf`, `y0`, `y0f`, `y1`, `y1f`, `yn`, `ynf` —
Bessel functions of first and second kind

# LIBRARY

Math Library (libm, -lm)

# SYNOPSIS

`#include <math.h>`

double
`j0`(double x);

float
`j0f`(float x);

double
`j1`(double x);

float
`j1f`(float x);

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

float
`jnf`(int n, float x);

double
`y0`(double x);

float
`y0f`(float x);

double
`y1`(double x);

float
`y1f`(float x);

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

float
`ynf`(int n, float x);

# DESCRIPTION

The functions `j0`(), `j0f`(), `j1`() and `j1f`() compute the Bessel function of the first kind of the order 0 and the order 1, respectively, for the real value x; the functions `jn`() and `jnf`() compute the Bessel function of the first kind of the integer order n for the real value x.

The functions `y0`(), `y0f`(), `y1`() and `y1f`() 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 functions `yn`() and `ynf`() compute the Bessel function of the second kind for the integer order n for the positive integer value x (expressed as a double).

# RETURN VALUES

If 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.

# SEE ALSO

math(3)

# HISTORY

This set of functions appeared in Version 7 AT&T UNIX.

April 19, 1991 | NetBSD 9.2