code: @Override boolean set_impl(int i, long l) {
      if( _ds   != null ) return set_impl(i,(double)l);
      if(_sparseLen != _len){ // sparse?
        int idx = Arrays.binarySearch(_id,0,_sparseLen,i);
        if(idx >= 0)i = idx;
        else cancel_sparse(); // for now don't bother setting the sparse value
      }
      _ls[i]=l; _xs[i]=0;
      _naCnt = -1;
      return true;
    }
docs: in-range and refer to the inflated values of the original Chunk.