ratexpand + pochhammer



maxima-bounces at math.utexas.edu wrote on 03/13/2009 01:48:57 PM:


> I have used pochhammer a lot for negative n too:
> 
> Pochhammer(a,-2) --> 1/((1-a) (2-a))
> 
> But there is a small problem. A lot of calculations which involve 
> more than one
> pochhammer function with positive and negative n would simplify 
muchbetter if
> 
> Pochhammer(a,-2) would give 1((a-2) (a-1))
> 
> To achieve this representation I have factored the result of pochhammer 
for
> negative n in some calculations.
> 
> Dieter Kaiser

Ahh, yes. There is a better reflection formula. I'll change this (not for 
the next release).

The revised simp-pochhammer will give the rectangular form for the pure 
numeric cases
without using rectform (thanks to numeric.lisp). And I think I'll change 
the code so that
max_pochhammer_index < -1 prevents all expansion, but otherwise not change 
the way
pochhammer works (or doesn't work :( .

Thanks for the suggestion.

Barton