Function rComposeOrder

Singular/ipshell.cc:2480–2778

}

static inline BOOLEAN rComposeOrder(const lists  L, const BOOLEAN check_comp, ring R)
{
  assume(R!=NULL);
  long bitmask=0L;
  if (L->m[2].Typ()==LIST_CMD)
  {
    lists v=(lists)L->m[2].Data();
    int n= v->nr+2;
    int j_in_R,j_in_L;
    // do we have an entry "L",... ?: set bitmask
    for (int j=0; j < n-1; j++)
    {
      if (v->m[j].Typ()==LIST_CMD)
      {
        lists vv=(lists)v->m[j].Data();
        if ((vv->nr==1)
        &&(vv->m[0].Typ()==STRING_CMD)
        &&(strcmp((char*)vv->m[0].Data(),"L")==0))
        {
          number nn=(number)vv->m[1].Data();
          if (vv->m[1].Typ()==BIGINT_CMD)
            bitmask=n_Int(nn,coeffs_BIGINT);
          else if (vv->m[1].Typ()==INT_CMD)
            bitmask=(long)nn;
          else
          {
            Werror("illegal argument for pseudo ordering L: %d",vv->m[1].Typ());
            return TRUE;
          }
          break;
        }
      }
    }
    if (bitmask!=0) n--;

    // initialize fields of R
    R->order=(rRingOrder_t *)omAlloc0((n+1)*sizeof(rRingOrder_t));
    R->block0=(int *)omAlloc0((n+1)*sizeof(int));
    R->block1=(int *)omAlloc0((n+1)*sizeof(int));
    R->wvhdl=(int**)omAlloc0((n+1)*sizeof(int_ptr));
    // init order, so that rBlocks works correctly
    for (j_in_R= n-2; j_in_R>=0; j_in_R--)
      R->order[j_in_R] = ringorder_unspec;
    // orderings
    for(j_in_R=0,j_in_L=0;j_in_R<n-1;j_in_R++,j_in_L++)
    {
    // todo: a(..), M
      if (v->m[j_in_L].Typ()!=LIST_CMD)
      {
        WerrorS("ordering must be list of lists");
        return TRUE;
      }
      lists vv=(lists)v->m[j_in_L].Data();
      if ((vv->nr==1)
      && (vv->m[0].Typ()==STRING_CMD))
      {
        if (strcmp((char*)vv->m[0].Data(),"L")==0)
        {