Camm Maguire wrote:
> Greetings, and thanks for these pointers! There are probably other
> functions that need attention as well. In any case, we should be
> encouraged that the original version basically had the scaling issue
> down.
>
> Here is what I've just committed:
>
> (defun acosh (x)
> (* 2 (log (+ (sqrt (/ (1+ x) 2)) (sqrt (/ (1- x) 2))))))
>
Although this doesn't help in the case where x is real, but you might be
interested in looking at the routines in CMUCL (see src/irrat.lisp) for
these functions for complex args. They're translations of the routines
in Kahan's article that Barton references.
Ray