CHEBYSHEV SERIES APPROXIMATIONS FOR THE BESSEL-FUNCTION Y-N(Z) OF COMPLEX ARGUMENT

We employ the truncated Chebyshev series to approximate the Bessel fun ction of the second kind Y-n(z) for \z\ less than or equal to 8. Detai led manipulations and discussions for Y-0(z) and Y-1(z) are given. Res ults of numerical experiments are presented to demonstrate the compute d accuracy by using the Chebyshev series approximations. Advantages an d disadvantages of the Chebyshev series approximation compared with ot her polynomial approximation methods, e.g., the tau-method approximati ons, are discussed. (C) Elsevier Science Inc., 1997.