ROL_HS4.hpp

Go to the documentation of this file.

// @HEADER
// *****************************************************************************
//               Rapid Optimization Library (ROL) Package
//
// Copyright 2014 NTESS and the ROL contributors.
// SPDX-License-Identifier: BSD-3-Clause
// *****************************************************************************
// @HEADER

#ifndef USE_HESSVEC 
#define USE_HESSVEC 1
#endif

#ifndef ROL_HS4_HPP
#define ROL_HS4_HPP

#include "ROL_StdVector.hpp"
#include "ROL_TestProblem.hpp"
#include "ROL_Bounds.hpp"
#include "ROL_Types.hpp"

namespace ROL {
namespace ZOO {

  template<class Real>
  class Objective_HS4 : public Objective<Real> {

    typedef std::vector<Real> vector;
    typedef Vector<Real>      V;
    typedef StdVector<Real>   SV;

  private:

    ROL::Ptr<const vector> getVector( const V& x ) {
      
      return dynamic_cast<const SV&>(x).getVector(); 
    }
   
    ROL::Ptr<vector> getVector( V& x ) {
      
      return dynamic_cast<SV&>(x).getVector();
    }

  public:
    Objective_HS4(void) {}

    Real value( const Vector<Real> &x, Real &tol ) {
      
      ROL::Ptr<const vector> ex = getVector(x);    

      return 1.0/3.0 * std::pow((*ex)[0] + 1.0,3.0) + (*ex)[1];
    }

    void gradient( Vector<Real> &g, const Vector<Real> &x, Real &tol ) {
      
      ROL::Ptr<const vector> ex = getVector(x);
      ROL::Ptr<vector> eg = getVector(g);

      (*eg)[0] = std::pow((*ex)[0] + 1.0,2.0);
      (*eg)[1] = 1.0;
    }
#if USE_HESSVEC
    void hessVec( Vector<Real> &hv, const Vector<Real> &v, const Vector<Real> &x, Real &tol ) {
      
      ROL::Ptr<const vector> ex = getVector(x);
      ROL::Ptr<const vector> ev = getVector(v);
      ROL::Ptr<vector> ehv = getVector(hv);

      Real alpha = 0.0;
      (*ehv)[0] = 2.0*((*ex)[0] + 1.0)*(*ev)[0] + alpha*(*ev)[0];
      (*ehv)[1] = 0.0 + alpha*(*ev)[1];
    }
#endif
  };

template<class Real>
class getHS4 : public TestProblem<Real> {
public:
  getHS4(void) {}

  Ptr<Objective<Real>> getObjective(void) const {
    // Instantiate Objective Function
    return ROL::makePtr<Objective_HS4<Real>>();
  }

  Ptr<Vector<Real>> getInitialGuess(void) const {
    // Problem dimension
    int n = 2;
    // Get Initial Guess
    ROL::Ptr<std::vector<Real> > x0p = ROL::makePtr<std::vector<Real>>(n,0.0);
    (*x0p)[0] = 1.125; (*x0p)[1] = 0.125;
    return ROL::makePtr<StdVector<Real>>(x0p);
  }

  Ptr<Vector<Real>> getSolution(const int i = 0) const {
    // Problem dimension
    int n = 2;
    // Get Solution
    ROL::Ptr<std::vector<Real> > xp = ROL::makePtr<std::vector<Real>>(n,0.0);
    (*xp)[0] = 1.0; (*xp)[1] = 0.0;
    return ROL::makePtr<StdVector<Real>>(xp);
  }
 
  Ptr<BoundConstraint<Real>> getBoundConstraint(void) const {
    // Problem dimension
    int n = 2;
    // Instantiate BoundConstraint
    ROL::Ptr<std::vector<Real> > lp = ROL::makePtr<std::vector<Real>>(n,0.0);
    (*lp)[0] = 1.0; (*lp)[1] = 0.0;
    ROL::Ptr<Vector<Real> > l = ROL::makePtr<StdVector<Real>>(lp);
    ROL::Ptr<std::vector<Real> > up = ROL::makePtr<std::vector<Real>>(n,0.0);
    (*up)[0] = ROL_INF<Real>(); (*up)[1] = ROL_INF<Real>();
    ROL::Ptr<Vector<Real> > u = ROL::makePtr<StdVector<Real>>(up);
    return ROL::makePtr<Bounds<Real>>(l,u);
  }
};

} // End ZOO Namespace
} // End ROL Namespace

#endif