28 Numerics library [numerics]

28.7 Mathematical functions for floating-point types [c.math]

28.7.6 Mathematical special functions [sf.cmath]

28.7.6.20 Spherical Bessel functions of the first kind [sf.cmath.sph.bessel]

floating-point-type sph_bessel(unsigned n, floating-point-type x);
float        sph_besself(unsigned n, float x);
long double  sph_bessell(unsigned n, long double x);

Effects: These functions compute the spherical Bessel functions of the first kind of their respective arguments n and x.

Returns:

j_{n} (x)

, where

j_{n}

is given by Formula 28.40, n is n, and x is x.

\begin{matrix} j_{n} (x) = (π / 2 x)^{1 / 2} J_{n + 1 / 2} (x), for x \geq 0 \\ (28.40) \end{matrix}

Remarks: The effect of calling each of these functions is implementation-defined if n >= 128.