text: #ifndef _PRODUCT_LAPLACE_TPP_
  #define _PRODUCT_LAPLACE_TPP_
  
  
  //--------------------------------------------------------------------------
  template<class Point>
  double ProductLaplace::
  Eval(const Point &x, const Point &y, double lambda) const {
    if (x.GetD() != y.GetD()) {
      printf("ProductLaplace::Eval. Error: Point dimensions do not match. Return NAN.\n");
      return NAN;
    }
    double r1 = x.Dist1(y);
    double ret = s * exp(-r1/sigma);
    if (r1 == 0.0) {
      ret += lambda;
    }
    return ret;
  }
  
  
  #endif
  