Chi Chi_sub Ci Ci_sub Shi Shi_sub Si Si_sub

Ci_sub() Sub Ci_sub ( Ret As  Double, X As  Double, Optional Info As  Long  ) Cosine integral Ci(x) (Subroutine version) Purpose Computes the cosine integral. Ci(x) = -∫ cos(t)/t dt [x, ∞] Parameters [out] Ret Cosine integral Ci(x). [in] X Argument x. (X <> 0) (If x < 0, returns the real part = Ci(|x|)) [out] Info (Optional) = 0: Successful exit. = -1: The argument X had an illegal value. (X = 0) = 1: Floating point range error.