|Bill Allombert on Wed, 28 Jun 2006 20:56:07 +0200|
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|Re: divrem bug?|
On Wed, Jun 28, 2006 at 08:30:39PM +0200, Bernard Parisse wrote: > Bill Allombert wrote: > > >On Wed, Jun 28, 2006 at 02:58:57PM +0200, Bernard Parisse wrote: > > > >>Hi! > >> > >>under pari 2.3.0, divrem(x+1,x^2,y) returns > >>%1 = [1/y^2*x + 1/y^2, 0] > >> > >>It should be something corresponding to [(x+1)/x^2, 0], > >>y should not occur there. Or is it not handled under pari? > > > > > >Well returning incorrect output is a bug but I would not expect > >divrem(x+1,x^2,y) to work because this breaks variable priorities. > > > > Does it mean that divrem only works when the optionnal 3rd arg is the > main variable? In that case, the default argument should probably be > omitted. It works only if the optional 3rd arg has higher priority: ? divrem(y+1,y^2,x) %1 = [(y + 1)/y^2, 0]~ ? divrem(y+1,y^2,y) %2 = [0, y + 1]~ This still useful. > Otherwise, I believe that the fix should be in the C divrem function, > it should reorder variables before doing the division. Experimentally doing that almost always break something due to t_POLMOD objects. > I have a question about the documentation: currently I'm using > the short on-line doc available from src/language/init.h, but I would Please extract it from the pari.desc file instead. (We provide a perl module PARI::822 for that purpose). > like to have HTML online doc like for native xcas functions (currently > only in French), is there a way to convert the PARI tex doc using > something like latex2html? Please see <http://pari.math.u-bordeaux.fr/dochtml/html.stable/> However gphtml only display the long help of functions, not the manual body text. PARI doc is in TeX, not in LaTeX so latex2html will not work. Cheers, Bill.