vec_sort()

void Ring::vec_sort

(

vecterm *&

f

)

const

Definition at line 674 of file ring-vecs.cpp.

{
  // Internal routine to place the elements back in order after
  // an operation such as subvector.
  // Divide f into two lists of equal length, sort each,
  // then add them together.  This allows the same monomial
  // to appear more than once in 'f'.
 
  if (f == nullptr || f->next == nullptr) return;
  vecterm *f1 = nullptr;
  vecterm *f2 = nullptr;
  while (f != nullptr)
    {
      vecterm *t = f;
      f = f->next;
      t->next = f1;
      f1 = t;
 
      if (f == nullptr) break;
      t = f;
      f = f->next;
      t->next = f2;
      f2 = t;
    }
 
  vec_sort(f1);
  vec_sort(f2);
  add_vec_to(f1, f2);
  f = f1;
}

References add_vec_to(), vec::next, and vec_sort().

Referenced by coeffs_of_vec(), sub_vector(), vec_diff(), and vec_sort().