1J0(3) Linux Programmer's Manual J0(3)
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6 j0, j0f, j0l, j1, j1f, j1l, jn, jnf, jnl - Bessel functions of the
7 first kind
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10 #include <math.h>
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12 double j0(double x);
13 double j1(double x);
14 double jn(int n, double x);
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16 float j0f(float x);
17 float j1f(float x);
18 float jnf(int n, float x);
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20 long double j0l(long double x);
21 long double j1l(long double x);
22 long double jnl(int n, long double x);
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24 Link with -lm.
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26 Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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28 j0(), j1(), jn(): _SVID_SOURCE || _BSD_SOURCE || _XOPEN_SOURCE
29 j0f(), j0l(), j1f(), j1l(), jnf(), jnl(): _SVID_SOURCE || _BSD_SOURCE
30 || _XOPEN_SOURCE >= 600
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33 The j0() and j1() functions return Bessel functions of x of the first
34 kind of orders 0 and 1, respectively. The jn() function returns the
35 Bessel function of x of the first kind of order n.
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37 The j0f() etc. and j0l() etc. functions are versions that take and
38 return float and long double values, respectively.
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41 On success, these functions return the appropriate Bessel value of the
42 first kind for x.
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44 If x is a NaN, a NaN is returned.
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46 If x is too large in magnitude, or the result underflows, a range error
47 occurs, and the return value is 0.
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50 See math_error(7) for information on how to determine whether an error
51 has occurred when calling these functions.
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53 The following errors can occur:
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55 Range error: result underflow, or x is too large in magnitude
56 errno is set to ERANGE.
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58 These functions do not raise exceptions for fetestexcept(3).
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61 The functions returning double conform to SVr4, 4.3BSD, POSIX.1-2001.
62 The others are non-standard functions that also exist on the BSDs.
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65 There are errors of up to 2e-16 in the values returned by j0(), j1()
66 and jn() for values of x between -8 and 8.
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69 y0(3)
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72 This page is part of release 3.22 of the Linux man-pages project. A
73 description of the project, and information about reporting bugs, can
74 be found at http://www.kernel.org/doc/man-pages/.
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78 2008-08-05 J0(3)