Changeset 0e2f8c in git for factory

Timestamp:

Nov 13, 2013, 3:47:14 PM (10 years ago)

Author:

Hans Schoenemann <hannes@…>

Branches:

(u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')

Children:

39d427f4321691ff7ee982ea2a474bb8c09aacbb

Parents:

867d59cf46048ef5ad1c520db05b0b6d5f71d305

git-author:

Hans Schoenemann <hannes@mathematik.uni-kl.de>2013-11-13 15:47:14+01:00

git-committer:

Hans Schoenemann <hannes@mathematik.uni-kl.de>2013-11-13 15:48:47+01:00

Message:

fix: extgcd(x,x) fails with NTL: try without

File:

• factory/cf_gcd.cc (modified) (1 diff)

factory/cf_gcd.cc

@@ -392 +392 @@
       XGCD(RR,A,B,F1,G1,1);
       CanonicalForm rr=convertZZ2CF(RR);
-      ASSERT (!rr.isZero(), "NTL:XGCD failed");
-      a=convertNTLZZX2CF(A,f.mvar())*fc/rr;
-      b=convertNTLZZX2CF(B,f.mvar())*gc/rr;
-      return CanonicalForm(1);
-    }
-    else
-    {
-      fc=bCommonDen(f);
-      gc=bCommonDen(g);
-      F1=convertFacCF2NTLZZX(f*fc/r);
-      G1=convertFacCF2NTLZZX(g*gc/r);
+      if(!rr.isZero())
+      {
+        a=convertNTLZZX2CF(A,f.mvar())*fc/rr;
+        b=convertNTLZZX2CF(B,f.mvar())*gc/rr;
+        return CanonicalForm(1);
+      }
+      else
+      {
+        Off(SW_USE_NTL_GCD_0);
+        r=extgcd(f,g,a,b);
+        On(SW_USE_NTL_GCD_0);
+      }
+    }
+    else
+    {
       XGCD(RR,A,B,F1,G1,1);
-      a=convertNTLZZX2CF(A,f.mvar())*fc;
-      b=convertNTLZZX2CF(B,f.mvar())*gc;
       CanonicalForm rr=convertZZ2CF(RR);
-      ASSERT (!rr.isZero(), "NTL:XGCD failed");
-      a /= rr;
-      b /= rr;
+      if (!rr.isZero())
+      {
+        a=convertNTLZZX2CF(A,f.mvar())*fc;
+        b=convertNTLZZX2CF(B,f.mvar())*gc;
+      }
+      else
+      {
+        Off(SW_USE_NTL_GCD_0);
+        r=extgcd(f,g,a,b);
+        On(SW_USE_NTL_GCD_0);
+      }
       return r;
     }