Modified Bessel function of the first kind, ordern+½.
Loading LOADSUB ALL FROM "BESMS.HTS"
or LOADSUB FROM "MATHLIB.HTS"
Usage INTEGER N
REAL X,Y
Y=FNIhn(N,X)
Description
FNIhnreturns the value of the modified cylindrical Bessel function of the first kind and ordern+½ ofx,In+½(x).In+½(x) is defined for all values ofnand all positive values ofx. Ifnis positive or zero,In+½(x) is also defined forx= 0.
Errors
FNIhncauses an HTBasic error if its arguments are not of the types shown in the USAGE section, above, or ifxis out of the range of definition explained above.
See Also
In, Khn
In+½(x)
Note
The algorithm used computes the value ofIn+½ using a recursion from the values ofI½ andI1½. The computation time increases withnand the computation accuracy decreases withn.