gen_step()

int GB_comp::gen_step ( )

private

Definition at line 653 of file gb-homog2.cpp.

{
  s_pair *p = _gens->remove();
  if (p == nullptr) return SPAIR_DONE;
  if (p->degree != _this_degree)
    {
      _gens->put_back(p);
      return SPAIR_DONE;
    }
 
  _n_pairs_computed++;
  _n_gens_left--;
 
  compute_s_pair(p);
 
  gbvector *f = p->f;
  gbvector *fsyz = p->fsyz;
  p->f = nullptr;
  p->fsyz = nullptr;
  remove_pair(p);
 
  gb_reduce(f, fsyz);
  if (!_GR->gbvector_is_zero(f))
    {
      gb_insert(f, fsyz, 1);  // 1 = minimal generator
      return SPAIR_MINGEN;
    }
 
  if (!_GR->gbvector_is_zero(fsyz))
    {
      if (_collect_syz)
        {
          // vec fsyzvec = _GR->gbvector_to_vec(_Fsyz,fsyz);
          _syz.push_back(fsyz);
          _n_syz++;
          return SPAIR_SYZ;
        }
      else
        _GR->gbvector_remove(fsyz);
    }
 
  return SPAIR_ZERO;
}

References _collect_syz, _gens, _GR, _n_gens_left, _n_pairs_computed, _n_syz, _this_degree, compute_s_pair(), gb_insert(), gb_reduce(), p, remove_pair(), SPAIR_DONE, SPAIR_MINGEN, SPAIR_SYZ, and SPAIR_ZERO.

Referenced by start_computation().