Modified spherical Bessel function of the first and second kinds and order n.
Loading LOADSUB ALL FROM "BESMS.HTS"
or LOADSUB FROM "MATHLIB.HTS"
Usage INTEGER N
REAL X,Y
Y=FNS_in(N,X)
Description
FNS_inreturns the value of the modified spherical Bessel function of ordernofx,in(x). The function is called a function of the first kind ifnis positive and a function of the second kind ifnis negative.In(x) is defined for all values ofnand for all values ofx, but large absolute values ofxmay cause the result to be larger in magnitude than MAXREAL, the largest value representable.
Errors
FNS_incauses an HTBasic error if its arguments are not of the types listed in theUSAGEsection, above, or if the result would be larger than MAXREAL.
in(x)
See Also S_i0, S_i1, S_ihn, S_kn
Note
The algorithm used computes the value ofinusing a recursion from the values ofi0 andi1. The computation time increases withnand the computation accuracy decreases withn.