Am 13 Oct 2007 um 22:01 hat Richard Fateman geschrieben:
> I haven't looked at it, but I think I copied it from some continued fraction
> approximation in Hakmem, probably written out by Bill Gosper.
> There are likely faster-converging formulas known now.
It took me some time to find out, what series it was.
I found, that it was the Newton series based on
pi = 6*asin(1/2)
Meanwhile I was looking for a faster way to compute PI in Maxima.
The best I found is a some kind of Ramanujan series by Chudnovsky & Chudnovsky.
The computation mainly uses bignum calculations and is therefor faster than other
algorithms which are based on bigfloat calculations (e.g. Borwein's recursive algorithms).
I changed float.lisp/comppi and also wrote a new function float.lisp/compe which computes
E by some modified Taylor series.
Volker van Nek