===================================================================
RCS file: /home/cvs/OpenXM_contrib2/asir2018/engine/dist.c,v
retrieving revision 1.4
retrieving revision 1.6
diff -u -p -r1.4 -r1.6
--- OpenXM_contrib2/asir2018/engine/dist.c	2019/09/04 01:12:02	1.4
+++ OpenXM_contrib2/asir2018/engine/dist.c	2019/09/05 08:49:43	1.6
@@ -45,7 +45,7 @@
  * DEVELOPER SHALL HAVE NO LIABILITY IN CONNECTION WITH THE USE,
  * PERFORMANCE OR NON-PERFORMANCE OF THE SOFTWARE.
  *
- * $OpenXM: OpenXM_contrib2/asir2018/engine/dist.c,v 1.3 2019/08/21 00:37:47 noro Exp $
+ * $OpenXM: OpenXM_contrib2/asir2018/engine/dist.c,v 1.5 2019/09/04 05:32:10 noro Exp $
 */
 #include "ca.h"
 
@@ -3119,3 +3119,102 @@ int compdpm(VL vl,DPM p1,DPM p2)
   }
 }
 
+// p = ...+c*<<0,...0:pos>>+...
+DPM dpm_eliminate_term(DPM a,DPM p,Obj c,int pos)
+{
+  MP d0,d;
+  DMM m;
+  DP f;
+  DPM a1,p1,r;
+
+  if ( !a ) return 0;
+  d0 = 0;
+  for ( m = BDY(a); m; m = NEXT(m) )
+    if ( m->pos == pos ) {
+      NEXTMP(d0,d); d->dl = m->dl; arf_chsgn(m->c,&d->c);
+    }
+  if ( d0 ) {
+    NEXT(d) = 0; MKDP(NV(a),d0,f);
+    mulcdpm(CO,c,a,&a1);
+    mulobjdpm(CO,(Obj)f,p,&p1); 
+    adddpm(CO,a1,p1,&r);
+    return r;
+  } else
+    return a;
+}
+
+// <<...:i>> -> <<...:tab[i]>>
+DPM dpm_compress(DPM p,int *tab)
+{
+  DMM m,mr0,mr;
+  DPM t;
+
+  if ( !p ) return 0;
+  else {
+    for ( m = BDY(p), mr0 = 0; m; m = NEXT(m) ) {
+      NEXTDMM(mr0,mr);
+      mr->dl = m->dl; mr->c = m->c; mr->pos = tab[m->pos];
+      if ( mr->pos <= 0 )
+        error("dpm_compress : invalid position");
+    }
+    NEXT(mr) = 0;
+    MKDPM(p->nv,mr0,t); t->sugar = p->sugar;
+    return t;
+  }
+}
+
+// input : s, s = syz(m) output simplified s, m
+void dpm_simplify_syz(LIST s,LIST m,LIST *s1,LIST *m1)
+{
+  int lm,ls,i,j,pos;
+  DPM *am,*as;
+  DPM p;
+  DMM d;
+  Obj c;
+  int *tab;
+  NODE t,t1;
+
+  lm = length(BDY(m));
+  am = (DPM *)MALLOC((lm+1)*sizeof(DPM));
+  ls = length(BDY(s));
+  as = (DPM *)MALLOC(ls*sizeof(DPM));
+  for ( i = 1, t = BDY(m); i <= lm; i++, t = NEXT(t) ) am[i] = (DPM)BDY(t);
+  for ( i = 0, t = BDY(s); i < ls; i++, t = NEXT(t) ) as[i] = (DPM)BDY(t);
+
+  for ( i = 0; i < ls; i++ ) {
+    p = as[i];
+    if ( p == 0 ) continue;
+    for ( d = BDY(p); d; d = NEXT(d) ) if ( d->dl->td == 0 ) break;
+    if ( d ) {
+      c = d->c; pos = d->pos;
+      for ( j = 0; j < ls; j++ )
+        if ( j != i ) {
+          as[j] = dpm_eliminate_term(as[j],p,c,pos);
+        }
+      // remove m[i]
+      am[pos] = 0;
+      as[i] = 0;
+    }
+  }
+  // compress s
+  // create index table from am[]
+  // (0 0 * 0 * ...) -> (0 0 1 0 2 ... ) which means 2->1, 4->2, ...
+  tab = (int *)MALLOC((lm+1)*sizeof(int));
+  for ( j = 0, i = 1; i <= lm; i++ ) {
+    if ( am[i] ) { j++; tab[i] = j; }
+    else tab[i] = 0;
+  }
+  t = 0;
+  for ( i = ls-1; i >= 0; i-- )
+    if ( as[i] ) {
+      p = dpm_compress(as[i],tab);
+      MKNODE(t1,(pointer)p,t); t = t1;
+    }
+  MKLIST(*s1,t);
+  t = 0;
+  for ( i = lm; i >= 1; i-- )
+    if ( am[i] ) {
+      MKNODE(t1,(pointer)am[i],t); t = t1;
+    }
+  MKLIST(*m1,t);
+}