Free Knowledge Resources


Linux Manual Pages


Free Software * Books

Source Code

Free Media

Linux

j0(3)


NAME

   j0,  j0f,  j0l,  j1,  j1f,  j1l, jn, jnf, jnl - Bessel functions of the
   first kind

SYNOPSIS

   #include <math.h>

   double j0(double x);
   double j1(double x);
   double jn(int n, double x);

   float j0f(float x);
   float j1f(float x);
   float jnf(int n, float x);

   long double j0l(long double x);
   long double j1l(long double x);
   long double jnl(int n, long double x);

   Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

   j0(), j1(), jn():
       _XOPEN_SOURCE
           || /* Since glibc 2.19: */ _DEFAULT_SOURCE
           || /* Glibc versions <= 2.19: */ _SVID_SOURCE || _BSD_SOURCE
   j0f(), j0l(), j1f(), j1l(), jnf(), jnl():
       _XOPEN_SOURCE  >= 600
           || (_ISOC99_SOURCE && _XOPEN_SOURCE)
           || /* Since glibc 2.19: */ _DEFAULT_SOURCE
           || /* Glibc versions <= 2.19: */ _SVID_SOURCE || _BSD_SOURCE

DESCRIPTION

   The j0() and j1() functions return Bessel functions of x of  the  first
   kind  of  orders  0 and 1, respectively.  The jn() function returns the
   Bessel function of x of the first kind of order n.

   The j0f(), j1f(), and jnf(),  functions  are  versions  that  take  and
   return  float  values.   The  j0l(),  j1l(),  and  jnl()  functions are
   versions that take and return long double values.

RETURN VALUE

   On success, these functions return the appropriate Bessel value of  the
   first kind for x.

   If x is a NaN, a NaN is returned.

   If x is too large in magnitude, or the result underflows, a range error
   occurs, and the return value is 0.

ERRORS

   See math_error(7) for information on how to determine whether an  error
   has occurred when calling these functions.

   The following errors can occur:

   Range error: result underflow, or x is too large in magnitude
          errno is set to ERANGE.

   These functions do not raise exceptions for fetestexcept(3).

ATTRIBUTES

   For   an   explanation   of   the  terms  used  in  this  section,  see
   attributes(7).

   
   Interface           Attribute      Value   
   
   j0(), j0f(), j0l()  Thread safety  MT-Safe 
   
   j1(), j1f(), j1l()  Thread safety  MT-Safe 
   
   jn(), jnf(), jnl()  Thread safety  MT-Safe

CONFORMING TO

   The functions returning double conform to SVr4,  4.3BSD,  POSIX.1-2001,
   and POSIX.1-2008.  The others are nonstandard functions that also exist
   on the BSDs.

BUGS

   There are errors of up to 2e-16 in the values returned  by  j0(),  j1()
   and jn() for values of x between -8 and 8.

SEE ALSO

   y0(3)

COLOPHON

   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at
   https://www.kernel.org/doc/man-pages/.

                              2016-03-15                             J0(3)



Opportunity


Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.

Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.



Free Software


Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.

Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.



Free Books


The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.

Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.



Education


Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.

Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.


birds banner