===================================================================
RCS file: /home/cvs/OpenXM/src/kan96xx/Kan/sugar.c,v
retrieving revision 1.1.1.1
retrieving revision 1.6
diff -u -p -r1.1.1.1 -r1.6
--- OpenXM/src/kan96xx/Kan/sugar.c	1999/10/08 02:12:02	1.1.1.1
+++ OpenXM/src/kan96xx/Kan/sugar.c	2003/09/12 02:52:50	1.6
@@ -1,3 +1,4 @@
+/* $OpenXM: OpenXM/src/kan96xx/Kan/sugar.c,v 1.5 2003/08/21 02:30:23 takayama Exp $ */
 #include <stdio.h>
 #include "datatype.h"
 #include "extern2.h"
@@ -5,10 +6,14 @@
 
 #define mymax(p,q) (p>q?p:q)
 
-static int DebugReduction = 0;
+/* static int DebugReduction = 0; 
+*/
+extern DebugReductionRed;
+extern DebugContentReduction;
+extern Ecart;
 
 POLY reduction_sugar(POLY f,struct gradedPolySet *gset,int needSyz,
-		     struct syz0 *syzp,int sugarGrade)
+                     struct syz0 *syzp,int sugarGrade)
 {
   int reduced,reduced1,reduced2;
   int grd;
@@ -21,13 +26,21 @@ POLY reduction_sugar(POLY f,struct gradedPolySet *gset
 
   extern struct ring *CurrentRingp;
   struct ring *rp;
-  
+  extern DoCancel;
+
+  if (Ecart) return reduction_ecart(f,gset,needSyz,syzp);
   if (needSyz) {
     if (f ISZERO) { rp = CurrentRingp; } else { rp = f->m->ringp; }
     cf = cxx(1,0,0,rp);
     syz = ZERO;
   }
 
+  if (needSyz && DoCancel) {
+	warningGradedSet("needSyz is not supported when DoCancel is turned on. DoCancel is set to 0.\n");
+	DoCancel = 0;
+  }
+  if (DoCancel && (f != POLYNULL)) shouldReduceContent(f,1);
+
   reduced = 0; /* no */
   /* Take minimum */
   gradelimit = (gset->maxGrade < sugarGrade+1 ?gset->maxGrade: sugarGrade+1);
@@ -37,44 +50,63 @@ POLY reduction_sugar(POLY f,struct gradedPolySet *gset
     while (grd < gset->maxGrade) {
       set = gset->polys[grd];
       do {
-	reduced2 = 0; /* no */
-	for (i=0; i<set->size; i++) {
-	  if (f ISZERO) goto ss;
-	  if ((*isReducible)(f,set->g[i])) {
-	    tdegm = grade_gen(f) - grade_gen(set->g[i]);
-	    /* Reduce if and only if sugarGrade does not increase. */
-	    if (tdegm+grd <= sugarGrade) {
-	      f = reduction1_sugar(f,set->g[i],needSyz,&cc,&cg,sugarGrade);
-	      if (needSyz) {
-		cf = ppMult(cc,cf);
-		syz = cpMult(toSyzCoeff(cc),syz);
-		syz = ppAddv(syz,toSyzPoly(cg,grd,i));
-	      }
-	      reduced = reduced1 = reduced2 = 1; /* yes */
-	    }
-	  }
-	}
+        reduced2 = 0; /* no */
+        for (i=0; i<set->size; i++) {
+          if (f ISZERO) goto ss;
+          if ((*isReducible)(f,set->g[i])) {
+            tdegm = grade_gen(f) - grade_gen(set->g[i]);
+            /* Reduce if and only if sugarGrade does not increase. */
+            if (tdegm+grd <= sugarGrade) {
+              f = reduction1_sugar(f,set->g[i],needSyz,&cc,&cg,sugarGrade);
+
+              if (DoCancel && (f != POLYNULL)) {
+                if (shouldReduceContent(f,0)) {
+                  struct coeff *cont;
+                  f = reduceContentOfPoly(f,&cont);
+                  shouldReduceContent(f,1);
+                  if (DebugContentReduction) printf("CONT=%s ",coeffToString(cont));
+                }
+              }
+
+              if (needSyz) {
+                cf = ppMult(cc,cf);
+                syz = cpMult(toSyzCoeff(cc),syz);
+                syz = ppAddv(syz,toSyzPoly(cg,grd,i));
+              }
+              reduced = reduced1 = reduced2 = 1; /* yes */
+            }
+          }
+        }
       } while (reduced2 != 0);
       grd++;
     }
   }while (reduced1 != 0);
 
-  ss: ;
+ ss: ;
   if (needSyz) {
     syzp->cf = cf;   /* cf is in the CurrentRingp */
     syzp->syz = syz; /* syz is in the SyzRingp */
   }
+
+  if (DoCancel && (f != POLYNULL)) {
+    if (f->m->ringp->p == 0) {
+	  struct coeff *cont;
+	  f = reduceContentOfPoly(f,&cont);
+	  if (DebugContentReduction) printf("cont=%s ",coeffToString(cont));     
+    }
+  }
+
   return(f);
 }
 
 POLY reduction1_sugar(f,g,needSyz,c,h,sugarGrade)
-POLY f;
-POLY g;
-int needSyz;
-POLY *c; /* set */
-POLY *h; /* set */
-int sugarGrade;
-/* f must be reducible by g.  r = c*f + h*g */
+     POLY f;
+     POLY g;
+     int needSyz;
+     POLY *c; /* set */
+     POLY *h; /* set */
+     int sugarGrade;
+     /* f must be reducible by g.  r = c*f + h*g */
 {
   extern struct ring *CurrentRingp;
   struct ring *rp;
@@ -91,9 +123,9 @@ int sugarGrade;
 
   sv = (*sp)(f,g);
   f2 = ppAddv(cpMult((sv.a)->coeffp,f),ppMult(sv.b,g));
-  if (DebugReduction) {
+  if (DebugReductionRed) {
     printf("c=%s, d=%s, g=%s:  f --> c*f + d*g.\n",
-	   POLYToString(sv.a,'*',1),POLYToString(sv.b,'*',1),POLYToString(g,'*',1));	   
+           POLYToString(sv.a,'*',1),POLYToString(sv.b,'*',1),POLYToString(g,'*',1));       
     printf("%s --> %s\n",POLYToString(f,'*',1),POLYToString(f2,'*',1));
   }
   f = f2;
@@ -109,15 +141,15 @@ int sugarGrade;
     if (tdegm+grd <= sugarGrade) {
       sv = (*sp)(f,g);
       f2 = ppAddv(cpMult((sv.a)->coeffp,f),ppMult(sv.b,g));
-      if (DebugReduction) {
-	printf("! c=%s, d=%s, g=%s:  f --> c*f + d*g.\n",
-	       POLYToString(sv.a,'*',1),POLYToString(sv.b,'*',1),POLYToString(g,'*',1));	   
-	printf("%s --> %s\n",POLYToString(f,'*',1),POLYToString(f2,'*',1));
+      if (DebugReductionRed) {
+        printf("! c=%s, d=%s, g=%s:  f --> c*f + d*g.\n",
+               POLYToString(sv.a,'*',1),POLYToString(sv.b,'*',1),POLYToString(g,'*',1));       
+        printf("%s --> %s\n",POLYToString(f,'*',1),POLYToString(f2,'*',1));
       }
       f = f2;
       if (needSyz) {
-	*c = ppMult(sv.a,*c);
-	*h = ppAdd(ppMult(sv.a,*h),sv.b);
+        *c = ppMult(sv.a,*c);
+        *h = ppAdd(ppMult(sv.a,*h),sv.b);
       }
     }else{
       break;
@@ -127,7 +159,7 @@ int sugarGrade;
 }
 
 int grade_sugar(f)
-POLY f;
+     POLY f;
 {
   int r;
   int i,ans;