Changeset fd803bc in git for factory/facHensel.cc

Timestamp:

Jul 14, 2011, 12:42:02 PM (13 years ago)

Author:

Martin Lee <martinlee84@…>

Branches:

(u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')

Children:

3ec4fce5af220b0b3987bf0805e36d89d4c5d9d9

Parents:

58b1160c31f60cc5b14e49848a7528f1889a1ba5

Message:

changes to Kronecker substitution multiplication


git-svn-id: file:///usr/local/Singular/svn/trunk@14334 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• factory/facHensel.cc (modified) (4 diffs)

factory/facHensel.cc

@@ -667 +667 @@
 
   mul (F2, F2, G2);
-  F2 >>= k;
+  if (deg (F2) > k)
+    F2 >>= (k - d1);
 
   return reverseSubst (F1, F2, d1, d2);
@@ -687 +688 @@
   int d2= tmax (degree (A, 2), degree (B, 2));
 
-  if (d1 > 128 && d2 > 160 && (degAy == degBy))
+  if (d1 > 128 && d2 > 160 && (degAy == degBy) && (2*degAy > degree (M)))
     return mulMod2NTLFpReci (A, B, M);
 
@@ -714 +715 @@
   kronSubRecipro (G1, G2, G, d1, alpha);
 
-  int k1= d1*degree (M);
-  MulTrunc (F1, F1, G1, (long) k1);
+  int k= d1*degree (M);
+  MulTrunc (F1, F1, G1, (long) k);
 
   mul (F2, F2, G2);
-
-  F2 >>= k1;
+  if (deg (F2) > k)
+    F2 >>= (k-d1);
 
   CanonicalForm result= reverseSubst (F1, F2, d1, d2, alpha);
@@ -747 +748 @@
 
     int degMipo= degree (getMipo (alpha));
-    if ((d1 > 128/degMipo) && (d2 > 160/degMipo) && (degAy == degBy))
+    if ((d1 > 128/degMipo) && (d2 > 160/degMipo) && (degAy == degBy) &&
+        (2*degAy > degree (M)))
       return mulMod2NTLFqReci (A, B, M, alpha);