Chu Chu_sub Hyp0f1 Hyp0f1_sub Hyp1f0 Hyp1f0_sub Hyp1f1 Hyp1f1_sub Hyp1f1r Hyp1f1r_sub Hyp2f0 Hyp2f0_sub Hyp2f1 Hyp2f1_sub Hyppfq Lhyp1f1 Lhyp1f1_sub

Chu() Function Chu ( A As  Double, B As  Double, X As  Double, Optional Info As  Long  ) Confluent hypergeometric function U(a, b, x) Purpose Computes the confluent hypergeometric function U(a, b, x). U(a, b, x) = (1/Γ(x)) * ∫ exp(-xt)t^(a-1)(1+t)^(b-a-1) dt [0, ∞] Returns Double Confluent hypergeometric function U(a, b, x) Parameters [in] A Argument a. [in] B Argument b. [in] X Argument x. (X >= 0) [out] Info (Optional) = 0: Successful exit. = -3: The argument X had an illegal value. (X < 0) = 1: Floating point range error. Note This program is not valid if 1 + a - b is close to zero when x is small.