Karim BELABAS on Mon, 8 Mar 1999 18:41:34 +0100 (MET)


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Re: pari-2.0.14 bugs


[Igor:]
> here's my current list of pari bugs.  Some of them were found after
> the release:
> 
> 2) nfgaloisconj(x^3+2,4)			\\ Infinite loop
> 3) poldiscreduced(polzagier(4,0))			\\ Error
> 6) nf=nfinit(x^2+1);idealred(nf,idealfactor(nf,2))	\\ SEGV
> 
> Bugs 2 and 6 are bad input bugs, hence of low priority.

Bug 3 is also of this sort, although the error message could be more
explicit, and the documentation ought to mention it: the polynomial has to
be integral and monic. Here's a cosmetic patch:

(18:40) gp > poldiscreduced(polzagier(4,0))    
  ***   non-monic polynomial in poldiscreduced.

Karim.

rc/basemath/polarit2.c.orig        Fri Mar  5 08:51:57 1999
--- src/basemath/polarit2.c     Mon Mar  8 18:40:08 1999
***************
*** 2114,2119 ****
--- 2114,2121 ----
    if (typ(pol)!=t_POL) err(typeer,"reduceddiscsmith");
    n=lgef(pol)-3;
    if (n<=0) err(constpoler,"reduceddiscsmith");
+   check_pol_int(pol);
+   if (!gcmp1(pol)) err(talker,"non-monic polynomial in poldiscreduced");
    polp = derivpol(pol); alpha = polx[varn(pol)];
    m=cgetg(n+1,t_MAT);
    for (j=1; j<=n; j++)
--
Karim Belabas                    email: Karim.Belabas@math.u-psud.fr
Dep. de Mathematiques, Bat. 425
Universite Paris-Sud             Tel: (00 33) 1 69 15 57 48
F-91405 Orsay (France)           Fax: (00 33) 1 69 15 60 19
--
PARI/GP Home Page: http://hasse.mathematik.tu-muenchen.de/ntsw/pari/