docs: private static void updateFilterSDASet(double mib, List<SteepDownArea> sdaset, double ixi) {
      Iterator<SteepDownArea> iter = sdaset.iterator();
      while(iter.hasNext()) {
        SteepDownArea sda = iter.next();
        if(sda.getMaximum() * ixi <= mib) {
          iter.remove();
        }
        else {
          // Update
          if(mib > sda.getMib()) {
            sda.setMib(mib);
          }
        }
      }
    }