static void retirer_doublons(Tab & tab, const T epsilon)
{
  int i = 0;
  int j;
  const int n = tab.size_array();
  T last_tab_i = -1e40;
  for (j = 0; j < n; j++) {
    const T x = tab[j];
    assert(x >= last_tab_i); // Array must be sorted
    if (x - last_tab_i > epsilon) {
      tab[i] = x;
      last_tab_i = x;
      i++;
    }
  }
  tab.resize_array(i);
}