'\"macro stdmacro
.if n .pH g3m.bessel @(#)bessel	40.9 of 10/10/89
.\" Copyright 1989 AT&T
.nr X
.if \nX=0 .ds x} bessel 3M "Math Libraries" "\&"
.if \nX=1 .ds x} bessel 3M "Math Libraries"
.if \nX=2 .ds x} bessel 3M "" "\&"
.if \nX=3 .ds x} bessel "" "" "\&"
.TH \*(x}
.SH NAME
\f4bessel\f2: \f4j0\f1, \f4j1\f1, \f4jn\f1, \f4y0\f1, \f4y1\f1, \f4yn\f1 \- Bessel functions
.SH SYNOPSIS
\f4cc\f1
[\f2flag\fP \|.\|.\|.] \f2file\fP \|.\|.\|.
\f4\-lm\f1
[\f2library\fP \|.\|.\|.]
.PP
\f4#include <math.h>\f1
.PP
\f4double j0 (double x);\f1
.PP
\f4double j1 (double x);\f1
.PP
\f4double jn (int n, double x);\f1
.PP
\f4double y0 (double x);\f1
.PP
\f4double y1 (double x);\f1
.PP
\f4double yn (int n, double x);\f1
.SH DESCRIPTION
\f4j0\fP
and
\f4j1\fP
return Bessel functions of
.I x\^
of the first kind of orders 0 and 1,
respectively.
\f4jn\fP
returns the Bessel function of
.I x\^
of the first kind of order
.IR n .
.PP
\f4y0\fP
and
\f4y1\fP
return Bessel functions of
.I x\^
of the second kind of orders 0 and 1, respectively.
\f4yn\fP
returns the Bessel function of
.I x\^
of the second kind of order
.IR n .
The value of
.I x\^
must be positive.
.SH SEE ALSO
\f4matherr\fP(3M).
.SH DIAGNOSTICS
Non-positive arguments cause
\f4y0\fP,
\f4y1\fP,
and
\f4yn\fP
to return the value
\f4\-HUGE\f1
and to set
\f4errno\fP
to
\f4EDOM\f1.
In addition, a message indicating
\f4DOMAIN\fP
error is printed on the standard error output.
.PP
Arguments too large in magnitude cause
\f4j0\fP, \f4j1\fP,
\f4y0\fP, and \f4y1\fP
to return 0 and to set
\f4errno\fP
to
\f4ERANGE\fP.
In addition, a message indicating
\f4TLOSS\fP
error is printed on the standard error output.
.PP
Except when the \f4\-Xc\fP compilation option is used,
these error-handling procedures may be changed with the function
\f4matherr\fP.
When the \f4\-Xa\f1 or \f4\-Xc\fP compilation options are used, 
\f4HUGE_VAL\fP
is returned instead of 
\f4HUGE\f1
and no error messages are printed.
.\"	@(#)bessel.3m	6.3 of 10/20/83
.Ee
