===================================================================
RCS file: /home/cvs/OpenXM/src/kan96xx/Kan/ecart.c,v
retrieving revision 1.8
retrieving revision 1.10
diff -u -p -r1.8 -r1.10
--- OpenXM/src/kan96xx/Kan/ecart.c	2003/08/19 08:02:09	1.8
+++ OpenXM/src/kan96xx/Kan/ecart.c	2003/08/20 05:18:35	1.10
@@ -1,4 +1,4 @@
-/* $OpenXM: OpenXM/src/kan96xx/Kan/ecart.c,v 1.7 2003/07/30 09:00:52 takayama Exp $ */
+/* $OpenXM: OpenXM/src/kan96xx/Kan/ecart.c,v 1.9 2003/08/20 01:39:17 takayama Exp $ */
 #include <stdio.h>
 #include "datatype.h"
 #include "extern2.h"
@@ -36,10 +36,12 @@ static POLY reduction_ecart1(POLY r,struct gradedPolyS
 static POLY reduction_ecart1_mod(POLY r,struct gradedPolySet *gset);
 static POLY  ecartCheckSyz0(POLY cf,POLY r_0,POLY syz,
                             struct gradedPolySet *gg,POLY r);
+static int shouldReduceContent(POLY f,int ss);
 
 extern int DebugReductionRed;
 extern int TraceLift;
 struct ring *TraceLift_ringmod;
+extern DoCancel;
 int DebugReductionEcart = 0;
 
 /* This is used for goHomogenization */
@@ -252,7 +254,7 @@ POLY reduction_ecart(r,gset,needSyz,syzp)
 		warningPoly("reduction_ecart: TraceLift_ringmod is not set.\n");
 		return reduction_ecart1(r,gset,needSyz,syzp);
 	  }
-	  rn = reduction_ecart1_mod(r,gset);
+	  rn = reduction_ecart1_mod(r,gset); /* BUG: syzygy is not obtained. */
 	  if (rn == POLYNULL) return rn;
 	  else return reduction_ecart1(r,gset,needSyz,syzp);
 	}else{
@@ -399,9 +401,11 @@ static POLY reduction_ecart1(r,gset,needSyz,syzp)
   POLY pp;
   int ell;
   int se;
+  struct coeff *cont;
 
   extern struct ring *CurrentRingp;
   struct ring *rp;
+  extern struct ring *SmallRingp;
 
   gg = NULL;
   if (needSyz) {
@@ -419,6 +423,7 @@ static POLY reduction_ecart1(r,gset,needSyz,syzp)
 
   r = goHomogenize11(r,DegreeShifto_vec,DegreeShifto_size,-1,1);
   /* 1 means homogenize only s */
+  if (DoCancel && (r != POLYNULL)) shouldReduceContent(r,1);
 
   if (DebugReductionEcart&1) printf("=======================================\n");
   do {
@@ -435,11 +440,20 @@ static POLY reduction_ecart1(r,gset,needSyz,syzp)
       if (ells.first) {
         pp = ((gset->polys[ells.grade])->gh)[ells.gseti];
       }else{
-        if (DebugReductionEcart & 4) printf("+");
+        if (DebugReductionEcart & 4) {printf("+"); fflush(NULL);}
         pp = (gg->pa)[ells.ggi];
       }
       if (ell > 0) r = mpMult(cxx(1,0,ell,rp),r); /* r = s^ell r */
       r = (*reduction1)(r,pp,needSyz,&cc,&cg);
+
+      if (DoCancel && (r != POLYNULL)) { /* BUG: syzygy should be corrected. */
+        if (shouldReduceContent(r,0)) {
+          r = reduceContentOfPoly(r,&cont);
+          shouldReduceContent(r,1);
+          if (DebugReductionEcart || DebugReductionRed) printf("CONT=%d ",coeffToString(cont));   
+        }
+      }
+
       if (needSyz) {
         if (ells.first) {
           cf = ppMult(cc,cf);
@@ -466,6 +480,14 @@ static POLY reduction_ecart1(r,gset,needSyz,syzp)
   }
 
   r = goDeHomogenizeS(r);
+  if (DoCancel && (r != POLYNULL)) { /* BUG: syzygy should be corrected. */
+    if (r->m->ringp->p == 0) {
+      if (coeffSizeMin(r) >= DoCancel) {
+        r = reduceContentOfPoly(r,&cont);
+        if (DebugReductionEcart || DebugReductionRed) printf("cont=%d ",coeffToString(cont));     
+      }
+    }
+  }
 
   return(r);
 }
@@ -598,7 +620,7 @@ static POLY reduction_ecart1_mod(r,gset)
       if (ells.first) {
         pp = ((gset->polys[ells.grade])->gmod)[ells.gseti];
       }else{
-        if (DebugReductionEcart & 4) printf("+");
+        if (DebugReductionEcart & 4) {printf("+"); fflush(NULL);}
         pp = (gg->pa)[ells.ggi];
       }
       if (ell > 0) r = mpMult(cxx(1,0,ell,rp),r); /* r = s^ell r */
@@ -613,4 +635,22 @@ static POLY reduction_ecart1_mod(r,gset)
   r = goDeHomogenizeS(r);
 
   return(r);
+}
+
+static int shouldReduceContent(POLY f,int ss) {
+  static int prevSize = 1;
+  int size;
+  if (f == POLYNULL) return 0;
+  if (f->m->ringp->p != 0) return 0;
+  if (f->coeffp->tag != MP_INTEGER) return 0;
+  size = mpz_size(f->coeffp->val.bigp);
+  if (ss > 0) {
+	prevSize = size;
+	return 0;
+  }
+  if (size > 2*prevSize) {
+	return 1;
+  }else{
+	return 0;
+  }
 }