Changeset d5cdf33 in git for libpolys/polys/clapsing.cc

Timestamp:

Sep 13, 2013, 2:15:30 PM (11 years ago)

Author:

Oleksandr Motsak <motsak@…>

Branches:

(u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')

Children:

4154bbc120e4fa4e98cdea1ae5c4cbb3e65e843aebf4609b3438506fccde45026d6628e1b7c7536a

Parents:

7627f67da8dc2c135f659c4e3f2ef25e3de4f00ebcaedabde8a91586f1c53635c29757100a6804ba

Message:

Merge pull request #371 from mmklee/cancellation

Cancellation

File:

• libpolys/polys/clapsing.cc (modified) (5 diffs)

libpolys/polys/clapsing.cc

@@ -147 +147 @@
 }
 
-void singclap_gcd_and_divide ( poly& f, poly& g, const ring r)
+poly singclap_gcd_and_divide ( poly& f, poly& g, const ring r)
 {
   poly res=NULL;
 
-  if (f!=NULL) p_Cleardenom(f, r);
-  if (g!=NULL) p_Cleardenom(g, r);
-  else         return; // g==0 => but do a p_Cleardenom(f)
-  if (f==NULL) return; // f==0 => but do a p_Cleardenom(g)
+  if (g == NULL)
+  {
+    res= p_Copy (f,r);
+    p_Delete (&f, r);
+    f=p_One (r);
+    return res;
+  }
+  if (f==NULL)
+  {
+    res= p_Copy (g,r);
+    p_Delete (&g, r);
+    g=p_One (r);
+    return res;
+  }
 
   Off(SW_RATIONAL);
@@ -169 +179 @@
       p_Delete(&f,r);
       p_Delete(&g,r);
-      f=convFactoryPSingP( F/GCD, r);
-      g=convFactoryPSingP( G/GCD, r);
-    }
+      if (getCharacteristic() == 0)
+        On (SW_RATIONAL);
+      F /= GCD;
+      G /= GCD;
+      if (getCharacteristic() == 0)
+      {
+        CanonicalForm denF= bCommonDen (F);
+        CanonicalForm denG= bCommonDen (G);
+        G *= denG;
+        F *= denF;
+        Off (SW_RATIONAL);
+        CanonicalForm gcddenFdenG= gcd (denG, denF);
+        denG /= gcddenFdenG;
+        denF /= gcddenFdenG;
+        On (SW_RATIONAL);
+        G *= denF;
+        F *= denG;
+      }
+      f=convFactoryPSingP( F, r);
+      g=convFactoryPSingP( G, r);
+    }
+    res=convFactoryPSingP( GCD , r);
     if (!b1) Off (SW_USE_EZGCD_P);
   }
@@ -193 +222 @@
         p_Delete(&f,r);
         p_Delete(&g,r);
-        f= convFactoryAPSingAP( F/GCD,r );
-        g= convFactoryAPSingAP( G/GCD,r );
-      }
+        if (getCharacteristic() == 0)
+          On (SW_RATIONAL);
+        F /= GCD;
+        G /= GCD;
+        if (getCharacteristic() == 0)
+        {
+          CanonicalForm denF= bCommonDen (F);
+          CanonicalForm denG= bCommonDen (G);
+          G *= denG;
+          F *= denF;
+          Off (SW_RATIONAL);
+          CanonicalForm gcddenFdenG= gcd (denG, denF);
+          denG /= gcddenFdenG;
+          denF /= gcddenFdenG;
+          On (SW_RATIONAL);
+          G *= denF;
+          F *= denG;
+        }
+        f= convFactoryAPSingAP( F,r );
+        g= convFactoryAPSingAP( G,r );
+      }
+      res= convFactoryAPSingAP( GCD,r );
       if (!b1) Off(SW_USE_QGCD);
     }
@@ -207 +255 @@
         p_Delete(&f,r);
         p_Delete(&g,r);
-        f= convFactoryPSingTrP( F/GCD,r );
-        g= convFactoryPSingTrP( G/GCD,r );
-      }
+        if (getCharacteristic() == 0)
+          On (SW_RATIONAL);
+        F /= GCD;
+        G /= GCD;
+        if (getCharacteristic() == 0)
+        {
+          CanonicalForm denF= bCommonDen (F);
+          CanonicalForm denG= bCommonDen (G);
+          G *= denG;
+          F *= denF;
+          Off (SW_RATIONAL);
+          CanonicalForm gcddenFdenG= gcd (denG, denF);
+          denG /= gcddenFdenG;
+          denF /= gcddenFdenG;
+          On (SW_RATIONAL);
+          G *= denF;
+          F *= denG;
+        }
+        f= convFactoryPSingTrP( F,r );
+        g= convFactoryPSingTrP( G,r );
+      }
+      res= convFactoryPSingTrP( GCD,r );
     }
   }
@@ -215 +282 @@
     WerrorS( feNotImplemented );
   Off(SW_RATIONAL);
+  return res;
 }