Hi Chris! On Sun, 23 Nov 2003 chrisd@sci.kun.nl wrote: [...]
I would say that the default behaviour of functions should be conjugate(f(arg)) --> f(conjugate(arg)). Then there should be a new function option to specify a different behaviour for your particular function. I was wondering a bit about what to do with the log. For that function the default behaviour is okay, except for the real negative axis.
Of course, exactly the same problems arise on other (analytic) functions with branch cuts. Take for instance asin(x) for real x where |x| > 1. But that shouldn't stop you.
I would say that just bluntly using the default behaviour, ignoring possible problems, would be best.
I guess that's right. What about non-analytic functions? We don't seem to have many, though, yet (just abs and csgn). Luck -richy. -- Richard B. Kreckel <Richard.Kreckel@GiNaC.DE> <http://www.ginac.de/~kreckel/>