Changeset 6b15a76 in git for libpolys

Timestamp:

Nov 19, 2018, 2:19:50 PM (5 years ago)

Author:

Hans Schoenemann <hannes@…>

Branches:

(u'fieker-DuVal', '117eb8c30fc9e991c4decca4832b1d19036c4c65')(u'spielwiese', 'd08f5f0bb3329b8ca19f23b74cb1473686415c3a')

Children:

38554beb085c7b26c5d00d8dd399ee6b5bb7bca8

Parents:

1bbd47fd39d8d0bee713b13b974dba118d689cd3

Message:

extend freeAlagebra to ordering a (+wp/Wp/dp/Dp) OR lp

Location:

libpolys/polys

Files:

• shiftop.cc (modified) (4 diffs)
• shiftop.h (modified) (1 diff)

libpolys/polys/shiftop.cc

@@ -735 +735 @@
 }
 
+/// substitute weights from orderings a,wp,Wp
+/// by d copies of it at position p
+static BOOLEAN freeAlgebra_weights(const ring old_ring, ring new_ring, int p, int d)
+{
+  omFree(new_ring->wvhdl[p]);
+  int *w=(int*)omAlloc(new_ring->N*sizeof(int));
+  for(int b=0;b<d;b++)
+  {
+    for(int i=old_ring->N-1;i>=0;i--)
+    {
+      if (old_ring->wvhdl[p][i]<-0) return TRUE;
+      w[b*old_ring->N+i]=old_ring->wvhdl[p][i];
+    }
+  }
+  new_ring->wvhdl[p]=w;
+  new_ring->block1[p]=new_ring->N;
+  return FALSE;
+}
+
 ring freeAlgebra(ring r, int d)
 {
@@ -747 +766 @@
   R->N=r->N*d;
   R->isLPring=r->N;
+  // create R->order
+  BOOLEAN has_order_a=FALSE;
+  while (r->order[p]==ringorder_a)
+  {
+    if (freeAlgebra_weights(r,R,p,d))
+    {
+      WerrorS("weights must be positive");
+      return NULL;
+    }
+    has_order_a=TRUE;
+    p++;
+  }
   R->block1[p]=R->N; /* only dp,Dp,wp,Wp; will be discarded for lp*/
-  // create R->order
   switch(r->order[p])
   {
@@ -756 +786 @@
     case ringorder_wp:
     case ringorder_Wp:
-    {
-      omFree(R->wvhdl[p]);
-      int *w=(int*)omAlloc(R->N*sizeof(int));
-      for(int b=1;b<d;b++)
+      if (freeAlgebra_weights(r,R,p,d))
       {
-        for(int i=r->N-1;i>=0;i--)
-          w[b*r->N+i]=r->wvhdl[p][i];
+        WerrorS("weights must be positive");
+        return NULL;
       }
-      R->wvhdl[p]=w;
       break;
-    }
     case ringorder_lp:
     case ringorder_rp:
     {
+      if(has_order_a)
+      {
+        WerrorS("ordering (a(..),lp/rp not implemented for LP-rings");
+        return NULL;
+      }
       int ** wvhdl=(int**)omAlloc0((r->N+2)*sizeof(int*));
       rRingOrder_t* ord=(rRingOrder_t*)omAlloc0((r->N+2)*sizeof(rRingOrder_t));
@@ -798 +828 @@
       // copy component order
       if (p==1) ord[0]=r->order[0];
-      else /*p==0*/ ord[r->N+1]=r->order[1];
+      else if (p==0) ord[r->N+1]=r->order[1];
+      else
+      { // should never happen:
+        WerrorS("ordering not implemented for LP-rings");
+        return NULL;
+      }
       break;
     }

libpolys/polys/shiftop.h

@@ -54 +54 @@
 poly p_LPVarAt(poly p, int pos, const ring r);
 
+/// create the letterplace ring corresponding to r up to degree d
 ring freeAlgebra(ring r, int d);
 #endif