realToComplexCast.hpp

/*
 * CoDiPack, a Code Differentiation Package
 *
 * Copyright (C) 2015-2025 Chair for Scientific Computing (SciComp), University of Kaiserslautern-Landau
 * Homepage: http://scicomp.rptu.de
 * Contact:  Prof. Nicolas R. Gauger (codi@scicomp.uni-kl.de)
 *
 * Lead developers: Max Sagebaum, Johannes Blühdorn (SciComp, University of Kaiserslautern-Landau)
 *
 * This file is part of CoDiPack (http://scicomp.rptu.de/software/codi).
 *
 * CoDiPack is free software: you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * CoDiPack is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU General Public License for more details.
 * You should have received a copy of the GNU
 * General Public License along with CoDiPack.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 * For other licensing options please contact us.
 *
 * Authors:
 *  - SciComp, University of Kaiserslautern-Landau:
 *    - Max Sagebaum
 *    - Johannes Blühdorn
 *    - Former members:
 *      - Tim Albring
 */
#pragma once
 
#include <complex>
 
#include "../../config.h"
#include "../../misc/macros.hpp"
#include "../../traits/expressionTraits.hpp"
#include "../computeExpression.hpp"

namespace codi {
 
  struct ReduceToReal {};  

  template<typename T_ComplexReal>
  struct OperationRealToComplexCast : public UnaryOperation<T_ComplexReal, OperationRealToComplexCast<T_ComplexReal>> {
    public:
 
      using ComplexReal = CODI_DD(T_ComplexReal, std::complex<double>);  
      using Jacobian = ReduceToReal;                                     
 
      using Real = typename ComplexReal::value_type;  

      template<typename Arg>
      static CODI_INLINE ComplexReal primal(Arg const& arg) {
        return arg;
      }

      template<typename Tangent, typename Arg>
      static CODI_INLINE ComplexReal applyTangentArg(Tangent const& tangent, ComplexReal const& result,
                                                     Arg const& arg) {
        CODI_UNUSED(result, arg);
        return tangent;
      }

      template<typename Adjoint, typename Arg>
      static CODI_INLINE Real applyAdjointArg(Adjoint const& adjoint, ComplexReal const& result, Arg const& arg) {
        CODI_UNUSED(result, arg);
 
        return adjoint.real();
      }

      static CODI_INLINE std::string getMathRep() {
        return "()";
      }
  };

  template<typename T_Real, typename T_Arg>
  using RealToComplexCast = ComputeExpression<std::complex<T_Real>, OperationRealToComplexCast, T_Arg>;
}