code: @Override
    public double[] toArray() {
      double[] data = new double[dimensionality];
      for(int i = BitsUtil.nextSetBit(bits, 0); i >= 0; i = BitsUtil.nextSetBit(bits, i + 1)) {
        data[i] = 1;
      }
      return data;
    }
docs: Returns a Vector representing in one column and
  <code>getDimensionality()</code> rows the values of this BitVector as
  double values.
  
  @return a Matrix representing in one column and
  <code>getDimensionality()</code> rows the values of this BitVector
  as double values
  
  @see de.lmu.ifi.dbs.elki.data.NumberVector#toArray()