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))))))
Take care,
willisb@unk.edu writes:
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> For a better acosh function, see
>
> http://www.mathworks.com/company/newsletter/clevescorner/sum98cleve.shtml
>
> And (but I haven't looked at it)
>
> Branch Cuts for Complex Elementary Functions, or Much Ado About Nothing's
> Sign Bit
> in The State of the Art in Numerical Analysis, (eds. Iserles and Powell),
> Clarendon Press, Oxford, 1987.
>
>
> Barton
>
>
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>
> <br><font size=2 face="Courier">For a better acosh function, see</font>
> <br>
> <br><font size=2 face="Courier">http://www.mathworks.com/company/newsletter/clevescorner/sum98cleve.shtml</font>;
> <br>
> <br><font size=2 face="Courier">And (but I haven't looked at it)</font>
> <br>
> <br><font size=2 face="Courier">Branch Cuts for Complex Elementary Functions, or Much Ado About Nothing's Sign Bit </font>
> <br><font size=2 face="Courier">in The State of the Art in Numerical Analysis, (eds. Iserles and Powell), Clarendon Press, Oxford, 1987. </font>
> <br>
> <br>
> <br><font size=2 face="Courier">Barton</font>
> <br>
> <br>
> --=_alternative 0070166386256C54_=--
>
>
--
Camm Maguire camm@enhanced.com
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