*** UNIX MANUAL PAGE BROWSER ***

bessel(3) Library Functions Manual bessel(3) NAME bessel, j0, j1, jn, y0, y1, yn - Compute Bessel functions LIBRARY Math Library (libm.a) 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); STANDARDS Interfaces documented on this reference page conform to industry stan- dards as follows: j0(): XPG4 j1(): XPG4 jn(): XPG4 y0(): XPG4 y1(): XPG4 yn(): XPG4 Refer to the standards(5) reference page for more information about in- dustry standards and associated tags. DESCRIPTION The j0(), j0f(), j1(), and j1f() functions return the value of the Bessel function of the first kind of orders 0 (zero) and 1, respec- tively. The jn() and jnf() functions return the value of the Bessel function of the first kind of order n. The y0(), y0f(), y1(), and y1f() functions return the value of the Bessel functions of the second kind of orders 0 (zero) and 1, respec- tively. The yn() and ynf() functions return the value of the Bessel function of the second kind of order n. The following table describes function behavior in response to excep- tional arguments: tab(@); lfHB lfHB lfHB lw(1.5i) lw(1.5i) lw(1.5i). _ Function@Exceptional Argument@Routine Behavior _ j0(), j1(), jn()@None@N/A j0f(), j1f(), jnf()@None@N/A y0(), y1(), yn()@x < 0@Invalid argument y0f(), y1f(), ynf()@x < 0@Invalid argument y0(), y1(), yn()@x = 0@Overflow y0f(), y1f(), ynf()@x = 0@Overflow _ The j1() and jn() functions can result in an underflow as x gets small. The largest value of x for which this occurs is a function of n. The y1() and yn() functions can result in an overflow as x gets small. The largest value of x for which this occurs is a function of n. delim off bessel(3)