complex conjugation

[Jens Vollinga]

Hi.

Concerning your complex conjugation patch (sorry for the late reply):

On Mon, Dec 08, 2003 at 10:29:37AM +0000, Chris Dams wrote:
> 
> Here is a patch that adds the operation of complex conjugation to GiNaC.
> On strings of gamma matrices, it acts as hermitian conjugation. On
> function the default behaviour is to complex conjugate all arguments of
> the function. A different behaviour can be specified by using a function
> option. The patch also includes my previous patch to for the expansion of
> muls and powers, because nobody seems to have read my mail about that yet.

The digestion of your contribution took a while, because the complex
conjugation of some functions (harmonic and multiple polylog) is a bit more
involved, and I wanted to think of a solution to this before integrating
the patch.

In doing so I recognized the following:
  sin(x).conjugate() gives sin(x) ?!
or simpler
  x.conjugate() gives x ?!
if x is symbol.

This seems to be a fundamental problem in my view. A possible solution
would be not to use a virtual function '.conjugate()', but instead to
use a Ginac-function 'ex conjugate(const ex&)', that only evaluates for
numerics and gamma matrices. This would also ease my headaches with those
polylogs ...

Comments, suggestions ?

Bye,
Jens