Function Approx_Step

kernel/GBEngine/nc.cc:250–415

ideal Approx_Step(ideal L)
{
  int N=currRing->N;
  int i,j; // k=syzcomp
  int flag, flagcnt=0, syzcnt=0;
  int syzcomp = 0;
  ideal I = kStd(L, currRing->qideal,testHomog,NULL,NULL,0,0,NULL);
  idSkipZeroes(I);
  ideal s_I;
  int idI = idElem(I);
  ideal trickyQuotient;
  if (currRing->qideal !=NULL)
  {
    trickyQuotient = idSimpleAdd(currRing->qideal,I);
  }
  else
    trickyQuotient = I;
  idSkipZeroes(trickyQuotient);
  poly *var = (poly *)omAlloc0((N+1)*sizeof(poly));
  //  poly *W = (poly *)omAlloc0((2*N+1)*sizeof(poly));
  resolvente S = (resolvente)omAlloc0((N+1)*sizeof(ideal));
  ideal SI, res;
  matrix MI;
  poly x=pOne();
  var[0]=x;
  ideal   h2, s_h2, s_h3;
  poly    p,q;
  // init vars
  for (i=1; i<=N; i++ )
  {
    x = pOne();
    pSetExp(x,i,1);
    pSetm(x);
    var[i]=pCopy(x);
  }
  // init NF's
  for (i=1; i<=N; i++ )
  {
    h2 = idInit(idI,1);
    flag = 0;
    for (j=0; j< idI; j++ )
    {
      q = pp_Mult_mm(I->m[j],var[i],currRing);
      q = kNF(I,currRing->qideal,q,0,0);
      if (q!=0)
      {
    h2->m[j]=pCopy(q);
    //  p_Shift(&(h2->m[flag]),1, currRing);
    flag++;
    pDelete(&q);
      }
      else
    h2->m[j]=0;
    }
    // W[1..IDELEMS(I)]
    if (flag >0)
    {
      // compute syzygies with values in I