integrate and pnz questions (progress?)



I would like to ask,
if there has been made some progress in the zeroa issue.
perhaps with a more recent maxima, i still have 5.15.0?

Regards
Andre

>stavros macrakis wrote:
>On Sat, Jan 24, 2009 at 11:08 AM, andre maute <andre.maute at gmx.de> wrote:
>> (%i3) integrate(x/(1-x),x,-1,1)
>> Is  zeroa  positive, negative, or zero?
>> what does zeroa mean here?
>
>zeroa is an internal symbol for a positive infinitesimal (sort of).
>The fact that it is being displayed to the user is a bug.  Anyway,
>asksign should know that zeroa>0 and zerob<0.
>
>> (%i3) integrate(1/x,x,-1,1)
>> Is  x-1  positive, negative, or zero?
>> ----------------------------------------------------------
>>
>> isn't x-1 < 1-1 = 0?
>> how does this pnz question help here?
>
>Yes, definite integration should be cleverer here.  Not exactly a bug,
>but not the best behavior.
>
>            -s


On Saturday 24 January 2009, andre maute wrote:
> I stumbled upon the following
>
> --------------------------------------------------------
> myuser at myhost:~$ maxima -b bug1.max
> Maxima 5.15.0 http://maxima.sourceforge.net
> Using Lisp SBCL 1.0.11.debian
> Distributed under the GNU Public License. See the file COPYING.
> Dedicated to the memory of William Schelter.
> The function bug_report() provides bug reporting information.
> (%i1)                           batch(bug1.max)
>
> batching /home/myuser/bug1.max
> (%i2)                          display2d : false
> (%o2) false
> (%i3) integrate(x/(1-x),x,-1,1)
> Is  zeroa  positive, negative, or zero?
> ----------------------------------------------------------
>
> what does zeroa mean here?
>
> ----------------------------------------------------------
> myuser at myhost:~$ maxima -b bug2.max
> Maxima 5.15.0 http://maxima.sourceforge.net
> Using Lisp SBCL 1.0.11.debian
> Distributed under the GNU Public License. See the file COPYING.
> Dedicated to the memory of William Schelter.
> The function bug_report() provides bug reporting information.
> (%i1)                           batch(bug2.max)
>
> batching /home/myuser/bug2.max
> (%i2)                          display2d : false
> (%o2) false
> (%i3) integrate(1/x,x,-1,1)
> Is  x-1  positive, negative, or zero?
> ----------------------------------------------------------
>
> isn't x-1 < 1-1 = 0?
> how does this pnz question help here?
>
> Regards Andre