Changeset c495ca in git for factory/cf_gcd.cc

Timestamp:

Feb 11, 2013, 11:17:23 AM (10 years ago)

Author:

Martin Lee <martinlee84@…>

Branches:

(u'jengelh-datetime', 'ceac47cbc86fe4a15902392bdbb9bd2ae0ea02c6')(u'spielwiese', '0604212ebb110535022efecad887940825b97c3f')

Children:

3a3393b2348060418dd1091d7fd2aeeec607740c

Parents:

1176ba0e57d133e7f6c1f50dca18b4170c0de3b6

git-author:

Martin Lee <martinlee84@web.de>2013-02-11 11:17:23+01:00

git-committer:

Martin Lee <martinlee84@web.de>2013-02-18 15:16:17+01:00

Message:

chg: some optimizations to psr gcd

File:

• factory/cf_gcd.cc (modified) (5 diffs)

factory/cf_gcd.cc

@@ -607 +607 @@
 gcd_poly_p( const CanonicalForm & f, const CanonicalForm & g )
 {
+    if (f.inCoeffDomain() || g.inCoeffDomain()) //zero case should be caught by gcd
+      return 1;
     CanonicalForm pi, pi1;
     CanonicalForm C, Ci, Ci1, Hi, bi, pi2;
-    bool bpure;
+    bool bpure, ezgcdon= isOn (SW_USE_EZGCD_P);
     int delta = degree( f ) - degree( g );
 
@@ -620 +622 @@
         pi = g; pi1 = f; delta = -delta;
     }
-    On (SW_USE_EZGCD_P);
-    Ci = content( pi ); Ci1 = content( pi1 );
-    Off (SW_USE_EZGCD_P);
-    pi1 = pi1 / Ci1; pi = pi / Ci;
+    if (pi.isUnivariate())
+      Ci= 1;
+    else
+    {
+      if (!ezgcdon)
+        On (SW_USE_EZGCD_P);
+      Ci = content( pi );
+      if (!ezgcdon)
+        Off (SW_USE_EZGCD_P);
+      pi = pi / Ci;
+    }
+    if (pi1.isUnivariate())
+      Ci1= 1;
+    else
+    {
+      if (!ezgcdon)
+        On (SW_USE_EZGCD_P);
+      Ci1 = content( pi1 );
+      if (!ezgcdon)
+        Off (SW_USE_EZGCD_P);
+      pi1 = pi1 / Ci1;
+    }
     C = gcd( Ci, Ci1 );
     int d= 0;
@@ -685 +705 @@
         pi = pi1; pi1 = pi2;
         maxNumVars= tmax (getNumVars (pi), getNumVars (pi1));
-        if (!(pi1.isUnivariate()) && (size (pi1)/maxNumVars > 500))
+        if (!pi1.isUnivariate() && (size (pi1)/maxNumVars > 500))
         {
             On (SW_USE_FF_MOD_GCD);
@@ -703 +723 @@
             if (!(pi.isUnivariate() && pi1.isUnivariate()))
             {
-              if (size (Hi)*size (pi)/(maxNumVars*3) > 500) //maybe this needs more tuning
+              if (size (Hi)*size (pi)/(maxNumVars*3) > 1500) //maybe this needs more tuning
               {
                 On (SW_USE_FF_MOD_GCD);
@@ -719 +739 @@
       return C;
     }
-    pi /= content( pi );
+    if (!pi.isUnivariate())
+    {
+      if (!ezgcdon)
+        On (SW_USE_EZGCD_P);
+      Ci= gcd (LC (oldPi,v), LC (oldPi1,v));
+      pi /= LC (pi,v)/Ci;
+      Ci= content (pi);
+      pi /= Ci;
+      if (!ezgcdon)
+        Off (SW_USE_EZGCD_P);
+    }
     if ( bpure )
         pi /= pi.lc();