Changeset 2156ec in git

Timestamp:

May 3, 2012, 12:10:05 PM (11 years ago)

Author:

Martin Lee <martinlee84@…>

Branches:

(u'spielwiese', '0d6b7fcd9813a1ca1ed4220cfa2b104b97a0a003')

Children:

0d56271c672440c06e14ca2528a5185bb37e1e6f

Parents:

e2666785b249262bbfdcdc9e4ca1a39a4054e994

git-author:

Martin Lee <martinlee84@web.de>2012-05-03 12:10:05+02:00

git-committer:

Martin Lee <martinlee84@web.de>2012-05-07 14:17:10+02:00

Message:

chg: compute content in QGCD

File:

• factory/algext.cc (modified) (7 diffs)

factory/algext.cc

@@ -24 +24 @@
 #include "cf_map.h"
 #include "cf_generator.h"
+
+#ifdef HAVE_NTL
+#include "NTLconvert.h"
+#endif
 
 /// compressing two polynomials F and G, M is used for compressing,
@@ -585 +589 @@
 }
 
+#ifdef HAVE_NTL
+static CanonicalForm
+myicontent ( const CanonicalForm & f, const CanonicalForm & c )
+{
+    if (f.isOne() || c.isOne())
+      return 1;
+    if ( f.inBaseDomain() && c.inBaseDomain())
+    {
+      if (c.isZero()) return abs(f);
+      return bgcd( f, c );
+    }
+    else if ( (f.inCoeffDomain() && c.inCoeffDomain()) ||
+              (f.inCoeffDomain() && c.inBaseDomain()) ||
+              (f.inBaseDomain() && c.inCoeffDomain()))
+    {
+      if (c.isZero()) return abs (f);
+      ZZX NTLf= convertFacCF2NTLZZX (f);
+      ZZX NTLc= convertFacCF2NTLZZX (c);
+      NTLc= GCD (NTLc, NTLf);
+      if (f.inCoeffDomain())
+        return convertNTLZZX2CF(NTLc,f.mvar());
+      else
+        return convertNTLZZX2CF(NTLc,c.mvar());
+    }
+    else
+    {
+        CanonicalForm g = c;
+        for ( CFIterator i = f; i.hasTerms() && ! g.isOne(); i++ )
+            g = myicontent( i.coeff(), g );
+        return g;
+    }
+}
+#endif
+
+CanonicalForm
+myicontent ( const CanonicalForm & f )
+{
+#ifdef HAVE_NTL
+    return myicontent( f, 0 );
+#else
+    return 1;
+#endif
+}
+
 CanonicalForm QGCD( const CanonicalForm & F, const CanonicalForm & G )
 { // f,g in Q(a)[x1,...,xn]
@@ -612 +660 @@
   f = F * bCommonDen(F);
   g = G * bCommonDen(G);
+  CanonicalForm contf= myicontent (f);
+  CanonicalForm contg= myicontent (g);
+  f /= contf;
+  g /= contg;
+  CanonicalForm gcdcfcg= myicontent (contf, contg);
   Variable a, b;
   if(hasFirstAlgVar(f,a))
@@ -627 +680 @@
       Off( SW_RATIONAL );
       Off( SW_USE_QGCD );
-      tmp = gcd( F, G );
+      tmp = gcdcfcg*gcd( f, g );
       On( SW_USE_QGCD );
       if (off_rational) Off(SW_RATIONAL);
@@ -682 +735 @@
       if (off_rational) Off(SW_RATIONAL); else On(SW_RATIONAL);
       setCharacteristic(0);
-      return CanonicalForm(1);
+      return gcdcfcg;
     }
     setCharacteristic(0);
@@ -712 +765 @@
         setReduce(a,true);
         if (off_rational) Off(SW_RATIONAL); else On(SW_RATIONAL);
-        return tmp;
+        return tmp*gcdcfcg;
       }
       Off( SW_RATIONAL );
@@ -729 +782 @@
   setReduce(a,true);
   Off( SW_USE_QGCD );
-  D = gcd( f, g );
+  D = gcdcfcg*gcd( f, g );
   On( SW_USE_QGCD );
   if (off_rational) Off(SW_RATIONAL); else On(SW_RATIONAL);