# j0(3) - NetBSD Manual Pages

Command: Section: Arch: Collection:
```J0(3)                   NetBSD 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 indepen-
dent 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, other-
wise the global variable errno is set to EDOM and a reserve operand fault
is generated.