@Override
  public double lengthDPE() throws java.lang.Exception {
    double dblDPE = 0.;

    for (org.drip.spline.segment.LatentStateResponseModel lsrm : _aLSRM) dblDPE += lsrm.lengthDPE();

    return dblDPE;
  }
  @Override
  public double bestFitDPE(final org.drip.spline.params.StretchBestFitResponse rbfr)
      throws java.lang.Exception {
    if (null == rbfr) return 0.;

    double dblDPE = 0.;

    for (org.drip.spline.segment.LatentStateResponseModel lsrm : _aLSRM)
      dblDPE += lsrm.bestFitDPE(rbfr.sizeToSegment(lsrm));

    return dblDPE;
  }
  @Override
  public double calcRightEdgeDerivative(final int iOrder) throws java.lang.Exception {
    org.drip.spline.segment.LatentStateResponseModel lsrm = _aLSRM[_aLSRM.length - 1];

    return lsrm.calcResponseValueDerivative(lsrm.right(), iOrder);
  }