Am Freitag, den 23.01.2009, 22:59 -0500 schrieb Raymond Toy:
> Dieter Kaiser wrote:
> > The problem is that after a call e.g. to the Maxima function $gamma we
> > get a back a Maxima number. To continue the calculation we need the
> > number with a type which is compatible to the calculation within the
> > package bigfloat. This number should not be in general a bigfloat, but a
> > float, CL complex, ... and a bigfloat type only for Maxima bigfloat
> > number.
> >
> > I think such a function has to be added.
> >
> >
> Ok. The function bigfloat:to will take a maxima number and convert it
> to a CL or BIGFLOAT number (real or complex) as expected. I also added
> bigfloat:bigfloat to make a bigfloat number (real or complex).
>
> The changes are checked in.
>
> Let me know if you run into other problems and I'll try to fix them soon.
Hello Ray,
it works fine. I have nearly completed the numerical algorithm for the
beta_incomplete function. It works for float and bigfloat numbers as
expected.
There is an open problem for complex numbers. bigfloat:to does not do
the correct conversion for pure imaginary numbers.
Two examples:
(%i36) :lisp (bigfloat:to (mul '$%i ($bfloat 1.0)))
NIL
(%i36) :lisp (bigfloat:to (mul '$%i 1.0))
NIL
Dieter Kaiser