Exemplo n.º 1
0
  SmartPtr<IpoptAlgorithm>
  AlgorithmBuilder::BuildBasicAlgorithm(const Journalist& jnlst,
                                        const OptionsList& options,
                                        const std::string& prefix)
  {
    DBG_START_FUN("AlgorithmBuilder::BuildBasicAlgorithm",
                  dbg_verbosity);

    bool mehrotra_algorithm;
    options.GetBoolValue("mehrotra_algorithm", mehrotra_algorithm, prefix);

    // Create the convergence check
    SmartPtr<ConvergenceCheck> convCheck =
      new OptimalityErrorConvergenceCheck();

    // Create the solvers that will be used by the main algorithm

    SmartPtr<SparseSymLinearSolverInterface> SolverInterface;
    std::string linear_solver;
    options.GetStringValue("linear_solver", linear_solver, prefix);
    bool use_custom_solver = false;
    if (linear_solver=="ma27") {
#ifndef COINHSL_HAS_MA27
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma27TSolverInterface();
      if (!LSL_isMA27available()) {
        char buf[256];
        int rc = LSL_loadHSL(NULL, buf, 255);
        if (rc) {
          std::string errmsg;
          errmsg = "Selected linear solver MA27 not available.\nTried to obtain MA27 from shared library \"";
          errmsg += LSL_HSLLibraryName();
          errmsg += "\", but the following error occured:\n";
          errmsg += buf;
          THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
        }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for MA27 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma27TSolverInterface();
#endif

    }
    else if (linear_solver=="ma57") {
#ifndef COINHSL_HAS_MA57
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma57TSolverInterface();
      if (!LSL_isMA57available()) {
        char buf[256];
        int rc = LSL_loadHSL(NULL, buf, 255);
        if (rc) {
          std::string errmsg;
          errmsg = "Selected linear solver MA57 not available.\nTried to obtain MA57 from shared library \"";
          errmsg += LSL_HSLLibraryName();
          errmsg += "\", but the following error occured:\n";
          errmsg += buf;
          THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
        }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for MA57 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma57TSolverInterface();
#endif

    }
    else if (linear_solver=="ma77") {
#ifndef COINHSL_HAS_MA77
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma77SolverInterface();
      if (!LSL_isMA77available()) {
        char buf[256];
        int rc = LSL_loadHSL(NULL, buf, 255);
        if (rc) {
          std::string errmsg;
          errmsg = "Selected linear solver HSL_MA77 not available.\nTried to obtain HSL_MA77 from shared library \"";
          errmsg += LSL_HSLLibraryName();
          errmsg += "\", but the following error occured:\n";
          errmsg += buf;
          THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
        }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for HSL_MA77 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma77SolverInterface();
#endif

    }
    else if (linear_solver=="ma86") {
#ifndef COINHSL_HAS_MA86
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma86SolverInterface();
      if (!LSL_isMA86available()) {
        char buf[256];
        int rc = LSL_loadHSL(NULL, buf, 255);
        if (rc) {
          std::string errmsg;
          errmsg = "Selected linear solver HSL_MA86 not available.\nTried to obtain HSL_MA86 from shared library \"";
          errmsg += LSL_HSLLibraryName();
          errmsg += "\", but the following error occured:\n";
          errmsg += buf;
          THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
        }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for HSL_MA86 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma86SolverInterface();
#endif

    }
    else if (linear_solver=="pardiso") {
#ifndef HAVE_PARDISO
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new PardisoSolverInterface();
      char buf[256];
      int rc = LSL_loadPardisoLib(NULL, buf, 255);
      if (rc) {
        std::string errmsg;
        errmsg = "Selected linear solver Pardiso not available.\nTried to obtain Pardiso from shared library \"";
        errmsg += LSL_PardisoLibraryName();
        errmsg += "\", but the following error occured:\n";
        errmsg += buf;
        THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for Pardiso has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new PardisoSolverInterface();
#endif

    }
    else if (linear_solver=="ma97") {
#ifndef COINHSL_HAS_MA97
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma97SolverInterface();
      if (!LSL_isMA97available()) {
        char buf[256];
        int rc = LSL_loadHSL(NULL, buf, 255);
        if (rc) {
          std::string errmsg;
          errmsg = "Selected linear solver HSL_MA97 not available.\nTried to obtain HSL_MA97 from shared library \"";
          errmsg += LSL_HSLLibraryName();
          errmsg += "\", but the following error occured:\n";
          errmsg += buf;
          THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
        }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for HSL_MA97 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma97SolverInterface();
#endif

    }
    else if (linear_solver=="wsmp") {
#ifdef HAVE_WSMP
      bool wsmp_iterative;
      options.GetBoolValue("wsmp_iterative", wsmp_iterative, prefix);
      if (wsmp_iterative) {
        SolverInterface = new IterativeWsmpSolverInterface();
      }
      else {
        SolverInterface = new WsmpSolverInterface();
      }
#else

      THROW_EXCEPTION(OPTION_INVALID,
                      "Selected linear solver WSMP not available.");
#endif

    }
    else if (linear_solver=="mumps") {
#ifdef COIN_HAS_MUMPS
      SolverInterface = new MumpsSolverInterface();
#else

      THROW_EXCEPTION(OPTION_INVALID,
                      "Selected linear solver MUMPS not available.");
#endif

    }
    else if (linear_solver=="custom") {
      ASSERT_EXCEPTION(IsValid(custom_solver_), OPTION_INVALID,
                       "Selected linear solver CUSTOM not available.");
      use_custom_solver = true;
    }

    SmartPtr<AugSystemSolver> AugSolver;
    if (use_custom_solver) {
      AugSolver = custom_solver_;
    }
    else {
      SmartPtr<TSymScalingMethod> ScalingMethod;
      std::string linear_system_scaling;
      if (!options.GetStringValue("linear_system_scaling",
                                  linear_system_scaling, prefix)) {
        // By default, don't use mc19 for non-HSL solvers, or HSL_MA97
        if (linear_solver!="ma27" && linear_solver!="ma57" && linear_solver!="ma77" && linear_solver!="ma86") {
          linear_system_scaling="none";
        }
      }
      if (linear_system_scaling=="mc19") {
#ifndef COINHSL_HAS_MC19
# ifdef HAVE_LINEARSOLVERLOADER
        ScalingMethod = new Mc19TSymScalingMethod();
        if (!LSL_isMC19available()) {
          char buf[256];
          int rc = LSL_loadHSL(NULL, buf, 255);
          if (rc) {
            std::string errmsg;
            errmsg = "Selected linear system scaling method MC19 not available.\n";
            errmsg += buf;
            THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
          }
        }
# else
        THROW_EXCEPTION(OPTION_INVALID, "Support for MC19 has not been compiled into Ipopt.");
# endif
#else
        ScalingMethod = new Mc19TSymScalingMethod();
#endif

      }
      else if (linear_system_scaling=="slack-based") {
        ScalingMethod = new SlackBasedTSymScalingMethod();
      }

      SmartPtr<SymLinearSolver> ScaledSolver =
        new TSymLinearSolver(SolverInterface, ScalingMethod);

      AugSolver = new StdAugSystemSolver(*ScaledSolver);
    }

    Index enum_int;
    options.GetEnumValue("hessian_approximation", enum_int, prefix);
    HessianApproximationType hessian_approximation =
      HessianApproximationType(enum_int);
    if (hessian_approximation==LIMITED_MEMORY) {
      std::string lm_aug_solver;
      options.GetStringValue("limited_memory_aug_solver", lm_aug_solver,
                             prefix);
      if (lm_aug_solver == "sherman-morrison") {
        AugSolver = new LowRankAugSystemSolver(*AugSolver);
      }
      else if (lm_aug_solver == "extended") {
        Index lm_history;
        options.GetIntegerValue("limited_memory_max_history", lm_history,
                                prefix);
        Index max_rank;
        std::string lm_type;
        options.GetStringValue("limited_memory_update_type", lm_type, prefix);
        if (lm_type == "bfgs") {
          max_rank = 2*lm_history;
        }
        else if (lm_type == "sr1") {
          max_rank = lm_history;
        }
        else {
          THROW_EXCEPTION(OPTION_INVALID, "Unknown value for option \"limited_memory_update_type\".");
        }
        AugSolver = new LowRankSSAugSystemSolver(*AugSolver, max_rank);
      }
      else {
        THROW_EXCEPTION(OPTION_INVALID, "Unknown value for option \"limited_memory_aug_solver\".");
      }
    }

    SmartPtr<PDPerturbationHandler> pertHandler;
    std::string lsmethod;
    options.GetStringValue("line_search_method", lsmethod, prefix);
    if (lsmethod=="cg-penalty") {
      pertHandler = new CGPerturbationHandler();
    }
    else {
      pertHandler = new PDPerturbationHandler();
    }
    SmartPtr<PDSystemSolver> PDSolver =
      new PDFullSpaceSolver(*AugSolver, *pertHandler);

    // Create the object for initializing the iterates Initialization
    // object.  We include both the warm start and the defaut
    // initializer, so that the warm start options can be activated
    // without having to rebuild the algorithm
    SmartPtr<EqMultiplierCalculator> EqMultCalculator =
      new LeastSquareMultipliers(*AugSolver);
    SmartPtr<IterateInitializer> WarmStartInitializer =
      new WarmStartIterateInitializer();
    SmartPtr<IterateInitializer> IterInitializer =
      new DefaultIterateInitializer(EqMultCalculator, WarmStartInitializer,
                                    AugSolver);

    SmartPtr<RestorationPhase> resto_phase;
    SmartPtr<RestoConvergenceCheck> resto_convCheck;

    // We only need a restoration phase object if we use the filter
    // line search
    if (lsmethod=="filter" || lsmethod=="penalty") {
      // Solver for the restoration phase
      SmartPtr<AugSystemSolver> resto_AugSolver =
        new AugRestoSystemSolver(*AugSolver);
      SmartPtr<PDPerturbationHandler> resto_pertHandler =
        new PDPerturbationHandler();
      SmartPtr<PDSystemSolver> resto_PDSolver =
        new PDFullSpaceSolver(*resto_AugSolver, *resto_pertHandler);

      // Convergence check in the restoration phase
      if (lsmethod=="filter") {
        resto_convCheck = new RestoFilterConvergenceCheck();
      }
      else if (lsmethod=="penalty") {
        resto_convCheck = new RestoPenaltyConvergenceCheck();
      }

      // Line search method for the restoration phase
      SmartPtr<RestoRestorationPhase> resto_resto =
        new RestoRestorationPhase();

      SmartPtr<BacktrackingLSAcceptor> resto_LSacceptor;
      std::string resto_lsacceptor;
      options.GetStringValue("line_search_method", resto_lsacceptor,
                             "resto."+prefix);
      if (resto_lsacceptor=="filter") {
        resto_LSacceptor = new FilterLSAcceptor(GetRawPtr(resto_PDSolver));
      }
      else if (resto_lsacceptor=="cg-penalty") {
        resto_LSacceptor = new CGPenaltyLSAcceptor(GetRawPtr(resto_PDSolver));
      }
      else if (resto_lsacceptor=="penalty") {
        resto_LSacceptor = new PenaltyLSAcceptor(GetRawPtr(resto_PDSolver));
      }
      SmartPtr<LineSearch> resto_LineSearch =
        new BacktrackingLineSearch(resto_LSacceptor, GetRawPtr(resto_resto),
                                   GetRawPtr(resto_convCheck));

      // Create the mu update that will be used by the restoration phase
      // algorithm
      SmartPtr<MuUpdate> resto_MuUpdate;
      std::string resto_smuupdate;
      if (!options.GetStringValue("mu_strategy", resto_smuupdate, "resto."+prefix)) {
        // Change default for quasi-Newton option (then we use adaptive)
        Index enum_int;
        if (options.GetEnumValue("hessian_approximation", enum_int, prefix)) {
          HessianApproximationType hessian_approximation =
            HessianApproximationType(enum_int);
          if (hessian_approximation==LIMITED_MEMORY) {
            resto_smuupdate = "adaptive";
          }
        }
      }

      std::string resto_smuoracle;
      std::string resto_sfixmuoracle;
      if (resto_smuupdate=="adaptive" ) {
        options.GetStringValue("mu_oracle", resto_smuoracle, "resto."+prefix);
        options.GetStringValue("fixed_mu_oracle", resto_sfixmuoracle, "resto."+prefix);
      }

      if (resto_smuupdate=="monotone" ) {
        resto_MuUpdate = new MonotoneMuUpdate(GetRawPtr(resto_LineSearch));
      }
      else if (resto_smuupdate=="adaptive") {
        SmartPtr<MuOracle> resto_MuOracle;
        if (resto_smuoracle=="loqo") {
          resto_MuOracle = new LoqoMuOracle();
        }
        else if (resto_smuoracle=="probing") {
          resto_MuOracle = new ProbingMuOracle(resto_PDSolver);
        }
        else if (resto_smuoracle=="quality-function") {
          resto_MuOracle = new QualityFunctionMuOracle(resto_PDSolver);
        }
        SmartPtr<MuOracle> resto_FixMuOracle;
        if (resto_sfixmuoracle=="loqo") {
          resto_FixMuOracle = new LoqoMuOracle();
        }
        else if (resto_sfixmuoracle=="probing") {
          resto_FixMuOracle = new ProbingMuOracle(resto_PDSolver);
        }
        else if (resto_sfixmuoracle=="quality-function") {
          resto_FixMuOracle = new QualityFunctionMuOracle(resto_PDSolver);
        }
        else {
          resto_FixMuOracle = NULL;
        }
        resto_MuUpdate =
          new AdaptiveMuUpdate(GetRawPtr(resto_LineSearch),
                               resto_MuOracle, resto_FixMuOracle);
      }

      // Initialization of the iterates for the restoration phase
      SmartPtr<EqMultiplierCalculator> resto_EqMultCalculator =
        new LeastSquareMultipliers(*resto_AugSolver);
      SmartPtr<IterateInitializer> resto_IterInitializer =
        new RestoIterateInitializer(resto_EqMultCalculator);

      // Create the object for the iteration output during restoration
      SmartPtr<OrigIterationOutput> resto_OrigIterOutput = NULL;
      //   new OrigIterationOutput();
      SmartPtr<IterationOutput> resto_IterOutput =
        new RestoIterationOutput(resto_OrigIterOutput);

      // Get the Hessian updater for the restoration phase
      SmartPtr<HessianUpdater> resto_HessUpdater;
      switch (hessian_approximation) {
      case EXACT:
        resto_HessUpdater = new ExactHessianUpdater();
        break;
      case LIMITED_MEMORY:
        // ToDo This needs to be replaced!
        resto_HessUpdater  = new LimMemQuasiNewtonUpdater(true);
        break;
      }

      // Put together the overall restoration phase IP algorithm
      SmartPtr<SearchDirectionCalculator> resto_SearchDirCalc;
      if (resto_lsacceptor=="cg-penalty") {
        resto_SearchDirCalc = new CGSearchDirCalculator(GetRawPtr(resto_PDSolver));
      }
      else {
        resto_SearchDirCalc = new PDSearchDirCalculator(GetRawPtr(resto_PDSolver));
      }

      SmartPtr<IpoptAlgorithm> resto_alg =
        new IpoptAlgorithm(resto_SearchDirCalc,
                           GetRawPtr(resto_LineSearch),
                           GetRawPtr(resto_MuUpdate),
                           GetRawPtr(resto_convCheck),
                           resto_IterInitializer,
                           resto_IterOutput,
                           resto_HessUpdater,
                           resto_EqMultCalculator);

      // Set the restoration phase
      resto_phase =
        new MinC_1NrmRestorationPhase(*resto_alg, EqMultCalculator);
    }

    // Create the line search to be used by the main algorithm
    SmartPtr<BacktrackingLSAcceptor> LSacceptor;
    if (lsmethod=="filter") {
      LSacceptor = new FilterLSAcceptor(GetRawPtr(PDSolver));
    }
    else if (lsmethod=="cg-penalty") {
      LSacceptor = new CGPenaltyLSAcceptor(GetRawPtr(PDSolver));
    }
    else if (lsmethod=="penalty") {
      LSacceptor = new PenaltyLSAcceptor(GetRawPtr(PDSolver));
    }
    SmartPtr<LineSearch> lineSearch =
      new BacktrackingLineSearch(LSacceptor,
                                 GetRawPtr(resto_phase), convCheck);

    // The following cross reference is not good: We have to store a
    // pointer to the lineSearch object in resto_convCheck as a
    // non-SmartPtr to make sure that things are properly deleted when
    // the IpoptAlgorithm return by the Builder is destructed.
    if (IsValid(resto_convCheck)) {
      resto_convCheck->SetOrigLSAcceptor(*LSacceptor);
    }

    // Create the mu update that will be used by the main algorithm
    SmartPtr<MuUpdate> MuUpdate;
    std::string smuupdate;
    if (!options.GetStringValue("mu_strategy", smuupdate, prefix)) {
      // Change default for quasi-Newton option (then we use adaptive)
      Index enum_int;
      if (options.GetEnumValue("hessian_approximation", enum_int, prefix)) {
        HessianApproximationType hessian_approximation =
          HessianApproximationType(enum_int);
        if (hessian_approximation==LIMITED_MEMORY) {
          smuupdate = "adaptive";
        }
      }
      if (mehrotra_algorithm)
        smuupdate = "adaptive";
    }
    ASSERT_EXCEPTION(!mehrotra_algorithm || smuupdate=="adaptive",
                     OPTION_INVALID,
                     "If mehrotra_algorithm=yes, mu_strategy must be \"adaptive\".");
    std::string smuoracle;
    std::string sfixmuoracle;
    if (smuupdate=="adaptive" ) {
      if (!options.GetStringValue("mu_oracle", smuoracle, prefix)) {
        if (mehrotra_algorithm)
          smuoracle = "probing";
      }
      options.GetStringValue("fixed_mu_oracle", sfixmuoracle, prefix);
      ASSERT_EXCEPTION(!mehrotra_algorithm || smuoracle=="probing",
                       OPTION_INVALID,
                       "If mehrotra_algorithm=yes, mu_oracle must be \"probing\".");
    }

    if (smuupdate=="monotone" ) {
      MuUpdate = new MonotoneMuUpdate(GetRawPtr(lineSearch));
    }
    else if (smuupdate=="adaptive") {
      SmartPtr<MuOracle> muOracle;
      if (smuoracle=="loqo") {
        muOracle = new LoqoMuOracle();
      }
      else if (smuoracle=="probing") {
        muOracle = new ProbingMuOracle(PDSolver);
      }
      else if (smuoracle=="quality-function") {
        muOracle = new QualityFunctionMuOracle(PDSolver);
      }
      SmartPtr<MuOracle> FixMuOracle;
      if (sfixmuoracle=="loqo") {
        FixMuOracle = new LoqoMuOracle();
      }
      else if (sfixmuoracle=="probing") {
        FixMuOracle = new ProbingMuOracle(PDSolver);
      }
      else if (sfixmuoracle=="quality-function") {
        FixMuOracle = new QualityFunctionMuOracle(PDSolver);
      }
      else {
        FixMuOracle = NULL;
      }
      MuUpdate = new AdaptiveMuUpdate(GetRawPtr(lineSearch),
                                      muOracle, FixMuOracle);
    }

    // Create the object for the iteration output
    SmartPtr<IterationOutput> IterOutput =
      new OrigIterationOutput();

    // Get the Hessian updater for the main algorithm
    SmartPtr<HessianUpdater> HessUpdater;
    switch (hessian_approximation) {
    case EXACT:
      HessUpdater = new ExactHessianUpdater();
      break;
    case LIMITED_MEMORY:
      // ToDo This needs to be replaced!
      HessUpdater  = new LimMemQuasiNewtonUpdater(false);
      break;
    }

    // Create the main algorithm
    SmartPtr<SearchDirectionCalculator> SearchDirCalc;
    if (lsmethod=="cg-penalty") {
      SearchDirCalc = new CGSearchDirCalculator(GetRawPtr(PDSolver));
    }
    else {
      SearchDirCalc = new PDSearchDirCalculator(GetRawPtr(PDSolver));
    }
    SmartPtr<IpoptAlgorithm> alg =
      new IpoptAlgorithm(SearchDirCalc,
                         GetRawPtr(lineSearch), MuUpdate,
                         convCheck, IterInitializer, IterOutput,
                         HessUpdater, EqMultCalculator);

    return alg;
  }
Exemplo n.º 2
0
SmartPtr<SymLinearSolver> AlgorithmBuilder::SymLinearSolverFactory(
   const Journalist&     jnlst,
   const OptionsList&    options,
   const std::string&    prefix
   )
{
   SmartPtr<SparseSymLinearSolverInterface> SolverInterface;
   std::string linear_solver;
   options.GetStringValue("linear_solver", linear_solver, prefix);
   if( linear_solver == "ma27" )
   {
#ifndef COINHSL_HAS_MA27
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma27TSolverInterface();
      if (!LSL_isMA27available())
      {
         char buf[256];
         int rc = LSL_loadHSL(NULL, buf, 255);
         if (rc)
         {
            std::string errmsg;
            errmsg = "Selected linear solver MA27 not available.\nTried to obtain MA27 from shared library \"";
            errmsg += LSL_HSLLibraryName();
            errmsg += "\", but the following error occured:\n";
            errmsg += buf;
            THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
         }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for MA27 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma27TSolverInterface();
#endif

   }
   else if( linear_solver == "ma57" )
   {
#ifndef COINHSL_HAS_MA57
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma57TSolverInterface();
      if (!LSL_isMA57available())
      {
         char buf[256];
         int rc = LSL_loadHSL(NULL, buf, 255);
         if (rc)
         {
            std::string errmsg;
            errmsg = "Selected linear solver MA57 not available.\nTried to obtain MA57 from shared library \"";
            errmsg += LSL_HSLLibraryName();
            errmsg += "\", but the following error occured:\n";
            errmsg += buf;
            THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
         }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for MA57 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma57TSolverInterface();
#endif

   }
   else if( linear_solver == "ma77" )
   {
#ifndef COINHSL_HAS_MA77
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma77SolverInterface();
      if (!LSL_isMA77available())
      {
         char buf[256];
         int rc = LSL_loadHSL(NULL, buf, 255);
         if (rc)
         {
            std::string errmsg;
            errmsg = "Selected linear solver HSL_MA77 not available.\nTried to obtain HSL_MA77 from shared library \"";
            errmsg += LSL_HSLLibraryName();
            errmsg += "\", but the following error occured:\n";
            errmsg += buf;
            THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
         }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for HSL_MA77 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma77SolverInterface();
#endif

   }
   else if( linear_solver == "ma86" )
   {
#ifndef COINHSL_HAS_MA86
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma86SolverInterface();
      if (!LSL_isMA86available())
      {
         char buf[256];
         int rc = LSL_loadHSL(NULL, buf, 255);
         if (rc)
         {
            std::string errmsg;
            errmsg = "Selected linear solver HSL_MA86 not available.\nTried to obtain HSL_MA86 from shared library \"";
            errmsg += LSL_HSLLibraryName();
            errmsg += "\", but the following error occured:\n";
            errmsg += buf;
            THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
         }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for HSL_MA86 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma86SolverInterface();
#endif

   }
   else if( linear_solver == "pardiso" )
   {
#ifndef HAVE_PARDISO
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new PardisoSolverInterface();
      char buf[256];
      int rc = LSL_loadPardisoLib(NULL, buf, 255);
      if (rc)
      {
         std::string errmsg;
         errmsg = "Selected linear solver Pardiso not available.\nTried to obtain Pardiso from shared library \"";
         errmsg += LSL_PardisoLibraryName();
         errmsg += "\", but the following error occured:\n";
         errmsg += buf;
         THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for Pardiso has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new PardisoSolverInterface();
#endif

   }
   else if( linear_solver == "ma97" )
   {
#ifndef COINHSL_HAS_MA97
# ifdef HAVE_LINEARSOLVERLOADER
      SolverInterface = new Ma97SolverInterface();
      if (!LSL_isMA97available())
      {
         char buf[256];
         int rc = LSL_loadHSL(NULL, buf, 255);
         if (rc)
         {
            std::string errmsg;
            errmsg = "Selected linear solver HSL_MA97 not available.\nTried to obtain HSL_MA97 from shared library \"";
            errmsg += LSL_HSLLibraryName();
            errmsg += "\", but the following error occured:\n";
            errmsg += buf;
            THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
         }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for HSL_MA97 has not been compiled into Ipopt.");
# endif
#else
      SolverInterface = new Ma97SolverInterface();
#endif

   }
   else if( linear_solver == "wsmp" )
   {
#ifdef HAVE_WSMP
      bool wsmp_iterative;
      options.GetBoolValue("wsmp_iterative", wsmp_iterative, prefix);
      if (wsmp_iterative)
      {
         SolverInterface = new IterativeWsmpSolverInterface();
      }
      else
      {
         SolverInterface = new WsmpSolverInterface();
      }
#else

      THROW_EXCEPTION(OPTION_INVALID, "Selected linear solver WSMP not available.");
#endif

   }
   else if( linear_solver == "mumps" )
   {
#ifdef COIN_HAS_MUMPS
      SolverInterface = new MumpsSolverInterface();
#else

      THROW_EXCEPTION(OPTION_INVALID, "Selected linear solver MUMPS not available.");
#endif

   }
   else if( linear_solver == "custom" )
   {
      SolverInterface = NULL;
   }

   SmartPtr<TSymScalingMethod> ScalingMethod;
   std::string linear_system_scaling;
   if( !options.GetStringValue("linear_system_scaling", linear_system_scaling, prefix) )
   {
      // By default, don't use mc19 for non-HSL solvers, or HSL_MA97
      if( linear_solver != "ma27" && linear_solver != "ma57" && linear_solver != "ma77" && linear_solver != "ma86" )
      {
         linear_system_scaling = "none";
      }
   }
   if( linear_system_scaling == "mc19" )
   {
#ifndef COINHSL_HAS_MC19
# ifdef HAVE_LINEARSOLVERLOADER
      ScalingMethod = new Mc19TSymScalingMethod();
      if (!LSL_isMC19available())
      {
         char buf[256];
         int rc = LSL_loadHSL(NULL, buf, 255);
         if (rc)
         {
            std::string errmsg;
            errmsg = "Selected linear system scaling method MC19 not available.\n";
            errmsg += buf;
            THROW_EXCEPTION(OPTION_INVALID, errmsg.c_str());
         }
      }
# else
      THROW_EXCEPTION(OPTION_INVALID, "Support for MC19 has not been compiled into Ipopt.");
# endif
#else
      ScalingMethod = new Mc19TSymScalingMethod();
#endif

   }
   else if( linear_system_scaling == "slack-based" )
   {
      ScalingMethod = new SlackBasedTSymScalingMethod();
   }

   SmartPtr<SymLinearSolver> ScaledSolver = new TSymLinearSolver(SolverInterface, ScalingMethod);
   return ScaledSolver;
}