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

#include<math.h>doublej0(doublex);doublej1(doublex);doublejn(intn,doublex);floatj0f(floatx);floatj1f(floatx);floatjnf(intn,floatx);longdoublej0l(longdoublex);longdoublej1l(longdoublex);longdoublejnl(intn,longdoublex);Link with-lm. Feature Test Macro Requirements for glibc (seefeature_test_macros(7)):j0(),j1(),jn(): _SVID_SOURCE || _BSD_SOURCE || _XOPEN_SOURCEj0f(),j0l(),j1f(),j1l(),jnf(),jnl(): _SVID_SOURCE || _BSD_SOURCE || _XOPEN_SOURCE >= 600

Thej0() andj1() functions return Bessel functions ofxof the first kind of orders 0 and 1, respectively. Thejn() function returns the Bessel function ofxof the first kind of ordern. Thej0f() etc. andj0l() etc. functions are versions that take and returnfloatandlongdoublevalues, respectively.

On success, these functions return the appropriate Bessel value of the first kind forx. Ifxis a NaN, a NaN is returned. Ifxis too large in magnitude, or the result underflows, a range error occurs, and the return value is 0.

Seemath_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, orxis too large in magnitudeerrnois set toERANGE. These functions do not raise exceptions forfetestexcept(3).

The functions returningdoubleconform to SVr4, 4.3BSD, POSIX.1-2001. The others are nonstandard functions that also exist on the BSDs.

There are errors of up to 2e-16 in the values returned byj0(),j1() andjn() for values ofxbetween -8 and 8.

y0(3)

This page is part of release 3.24 of the Linuxman-pagesproject. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. 2008-08-05