[Maxima-discuss] cf of non-sqrt fractional powers

[Stavros M. (Σ. Μ. <mac...@al...>]

​In 2007, a hack was added to the cf function to handle cases like 2^(1/10).

Unfortunately,

a) It is extremely slow for a^(1/n) for n much larger than 3. There is a
fix for that documented in the bug
<https://sourceforge.net/p/maxima/bugs/3449/>.

b) It is approximate -- it uses "floor", which invokes bfloat evaluation.
This is different from sqrt(CF), where an exact CF algorithm is used.

c) Even with the fix, cf(2^(1/10)),cflength:30 gets an error (because it is
approximate, presumably).

d) It isn't documented.

e) It interprets cflength differently from the rest of cf.

Let's please remove this awful code. If someone wants to calculate
cf(2^(1/10)), they can use cf(bfloat(2^(1/10))) with whatever fpprec they
want. It is after all using bfloat internally.