cc [ flags ] -I/usr/local/include file(s) -L/usr/local/lib -lmcw [ ... ] #include <mathcw.h> extern float sbk0f (float x); extern double sbk0 (double x); extern long double sbk0l (long double x); extern __float80 sbk0w (__float80 x); extern __float128 sbk0q (__float128 x); extern long_long_double sbk0ll (long_long_double x); extern decimal_float sbk0df (decimal_float x); extern decimal_double sbk0d (decimal_double x); extern decimal_long_double sbk0dl (decimal_long_double x); extern decimal_long_long_double sbk0dll (decimal_long_long_double x);
NB: Functions with prototypes containing underscores in type names may be available only with certain extended compilers.
The modified spherical Bessel functions provided by these software implementations are defined according to Chapter 10, Bessel Functions of Fractional Order, of the Handbook of Mathematical Functions, edited by Milton Abramowitz and Irene A. Stegun, National Bureau of Standards Applied Mathematics Series #55, US Department of Commerce, Washington, DC (1964).
The k(n,x) functions fall exponentially with increasing x, and underflow even with moderate x values. For that reason, there is a related family of functions that return values of this Bessel function reduced by a factor of exp(x); see sbks0(3CW).