rb_scm_evaluation.C

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// rbOOmit: An implementation of the Certified Reduced Basis method.
// Copyright (C) 2009, 2010 David J. Knezevic
 
// This file is part of rbOOmit.
 
// rbOOmit is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
 
// rbOOmit 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
// Lesser General Public License for more details.
 
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 
// Configuration data
#include "libmesh/libmesh_config.h"
 
// RBSCMEvaluation should only be available
// if SLEPc and GLPK support is enabled.
#if defined(LIBMESH_HAVE_SLEPC) && (LIBMESH_HAVE_GLPK)
 
// rbOOmit includes
#include "libmesh/rb_scm_evaluation.h"
#include "libmesh/rb_theta_expansion.h"
 
// libMesh includes
#include "libmesh/dof_map.h"
#include "libmesh/equation_systems.h"
#include "libmesh/getpot.h"
#include "libmesh/int_range.h"
#include "libmesh/libmesh_logging.h"
#include "libmesh/numeric_vector.h"
#include "libmesh/sparse_matrix.h"
#include "libmesh/xdr_cxx.h"
 
// For creating a directory
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
 
// glpk includes
#include <glpk.h>
 
namespace libMesh
{
 
RBSCMEvaluation::RBSCMEvaluation (const Parallel::Communicator & comm_in) :
  ParallelObject(comm_in)
{
  // Clear SCM data vectors
  B_min.clear();
  B_max.clear();
  C_J.clear();
  C_J_stability_vector.clear();
  SCM_UB_vectors.clear();
}
 
RBSCMEvaluation::~RBSCMEvaluation () = default;
 
void RBSCMEvaluation::set_rb_theta_expansion(RBThetaExpansion & rb_theta_expansion_in)
{
  rb_theta_expansion = &rb_theta_expansion_in;
}
 
RBThetaExpansion & RBSCMEvaluation::get_rb_theta_expansion()
{
  libmesh_error_msg_if(!rb_theta_expansion, "Error: rb_theta_expansion hasn't been initialized yet");
 
  return *rb_theta_expansion;
}
 
void RBSCMEvaluation::set_C_J_stability_constraint(unsigned int j, Real stability_const_in)
{
  libmesh_error_msg_if(j >= C_J_stability_vector.size(), "Error: Input parameter j is too large in set_C_J_stability_constraint.");
 
  // we assume that C_J_stability_vector is resized elsewhere
  // to be the same size as C_J.
  libmesh_assert_equal_to (C_J_stability_vector.size(), C_J.size());
 
  C_J_stability_vector[j] = stability_const_in;
}
 
Real RBSCMEvaluation::get_C_J_stability_constraint(unsigned int j) const
{
  libmesh_error_msg_if(j >= C_J_stability_vector.size(), "Error: Input parameter j is too large in get_C_J_stability_constraint.");
 
  return C_J_stability_vector[j];
}
 
void RBSCMEvaluation::set_SCM_UB_vector(unsigned int j, unsigned int q, Real y_q)
{
  // First make sure that j <= J
  libmesh_error_msg_if(j >= SCM_UB_vectors.size(), "Error: We must have j < J in set_SCM_UB_vector.");
 
  // Next make sure that q <= Q_a or Q_a_hat
  libmesh_error_msg_if(q >= SCM_UB_vectors[0].size(), "Error: q is too large in set_SCM_UB_vector.");
 
  SCM_UB_vectors[j][q] = y_q;
}
 
Real RBSCMEvaluation::get_SCM_UB_vector(unsigned int j, unsigned int q)
{
  // First make sure that j <= J
  libmesh_error_msg_if(j >= SCM_UB_vectors.size(), "Error: We must have j < J in get_SCM_UB_vector.");
  libmesh_error_msg_if(q >= SCM_UB_vectors[0].size(), "Error: q is too large in get_SCM_UB_vector.");
 
  return SCM_UB_vectors[j][q];
}
 
const RBParameters & RBSCMEvaluation::get_C_J_entry(unsigned int j)
{
  libmesh_error_msg_if(j >= C_J.size(), "Error: Input parameter j is too large in get_C_J.");
 
  return C_J[j];
}
 
Real RBSCMEvaluation::get_B_min(unsigned int q) const
{
  libmesh_error_msg_if(q >= B_min.size(), "Error: q is too large in get_B_min.");
 
  return B_min[q];
}
 
 
Real RBSCMEvaluation::get_B_max(unsigned int q) const
{
  libmesh_error_msg_if(q >= B_max.size(), "Error: q is too large in get_B_max.");
 
  return B_max[q];
}
 
void RBSCMEvaluation::set_B_min(unsigned int q, Real B_min_val)
{
  libmesh_error_msg_if(q >= B_min.size(), "Error: q is too large in set_B_min.");
 
  B_min[q] = B_min_val;
}
 
void RBSCMEvaluation::set_B_max(unsigned int q, Real B_max_val)
{
  libmesh_error_msg_if(q >= B_max.size(), "Error: q is too large in set_B_max.");
 
  B_max[q] = B_max_val;
}
 
Real RBSCMEvaluation::get_SCM_LB()
{
  LOG_SCOPE("get_SCM_LB()", "RBSCMEvaluation");
 
  // Initialize the LP
  glp_prob * lp;
  lp = glp_create_prob();
  glp_set_obj_dir(lp,GLP_MIN);
 
  // Add columns to the LP: corresponds to
  // the variables y_1,...y_Q_a.
  // These are the same for each \mu in the SCM
  // training set, hence can do this up front.
  glp_add_cols(lp,rb_theta_expansion->get_n_A_terms());
 
  for (unsigned int q=0; q<rb_theta_expansion->get_n_A_terms(); q++)
    {
      if (B_max[q] < B_min[q]) // Invalid bound, set as free variable
        {
          // GLPK indexing is not zero based!
          glp_set_col_bnds(lp, q+1, GLP_FR, 0., 0.);
        }
      else
        {
          // GLPK indexing is not zero based!
          glp_set_col_bnds(lp, q+1, GLP_DB, double(B_min[q]), double(B_max[q]));
        }
 
      // If B_max is not defined, just set lower bounds...
      //       glp_set_col_bnds(lp, q+1, GLP_LO, B_min[q], 0.);
    }
 
 
  // Add rows to the LP: corresponds to the auxiliary
  // variables that define the constraints at each
  // mu \in C_J_M
  unsigned int n_rows = cast_int<unsigned int>(C_J.size());
  glp_add_rows(lp, n_rows);
 
  // Now put current_parameters in saved_parameters
  save_current_parameters();
 
  unsigned int matrix_size = n_rows*rb_theta_expansion->get_n_A_terms();
  std::vector<int> ia(matrix_size+1);
  std::vector<int> ja(matrix_size+1);
  std::vector<double> ar(matrix_size+1);
  unsigned int count=0;
  for (unsigned int m=0; m<n_rows; m++)
    {
      set_current_parameters_from_C_J(m);
 
      // Set the lower bound on the auxiliary variable
      // due to the stability constant at mu_index
      glp_set_row_bnds(lp, m+1, GLP_LO, double(C_J_stability_vector[m]), 0.);
 
      // Now define the matrix that relates the y's
      // to the auxiliary variables at the current
      // value of mu.
      for (unsigned int q=0; q<rb_theta_expansion->get_n_A_terms(); q++)
        {
          count++;
 
          ia[count] = m+1;
          ja[count] = q+1;
 
          // This can only handle Reals right now
          ar[count] = double(libmesh_real( rb_theta_expansion->eval_A_theta(q,get_parameters()) ));
        }
    }
 
  // Now load the original parameters back into current_parameters
  // in order to set the coefficients of the objective function
  reload_current_parameters();
 
  glp_load_matrix(lp, matrix_size, ia.data(), ja.data(), ar.data());
 
  for (unsigned int q=0; q<rb_theta_expansion->get_n_A_terms(); q++)
    {
      glp_set_obj_coef(lp,q+1, double(libmesh_real( rb_theta_expansion->eval_A_theta(q,get_parameters()) )) );
    }
 
  // Use this command to initialize the basis for the LP
  // since default behavior is to use the basis from
  // the previous solve, but that might become singular
  // if we switch the order of constraints (as can
  // happen when we generate a new C_J_M)
  //lpx_cpx_basis(lp); //glp_cpx_basis(lp);
 
  glp_smcp parm;
  glp_init_smcp(&parm);
  parm.msg_lev = GLP_MSG_ERR;
  parm.meth = GLP_DUAL;
 
 
  // use the simplex method and solve the LP
  glp_simplex(lp, &parm);
 
  Real min_J_obj = glp_get_obj_val(lp);
 
  //   int simplex_status =  glp_get_status(lp);
  //   if (simplex_status == GLP_UNBND)
  //   {
  //     libMesh::out << "Simplex method gave unbounded solution." << std::endl;
  //     min_J_obj = std::numeric_limits<Real>::quiet_NaN();
  //   }
  //   else
  //   {
  //     min_J_obj = glp_get_obj_val(lp);
  //   }
 
  // Destroy the LP
  glp_delete_prob(lp);
 
  return min_J_obj;
}
 
Real RBSCMEvaluation::get_SCM_UB()
{
  LOG_SCOPE("get_SCM_UB()", "RBSCMEvaluation");
 
  // Add rows to the LP: corresponds to the auxiliary
  // variables that define the constraints at each
  // mu \in C_J
  unsigned int n_rows = cast_int<unsigned int>(C_J.size());
 
  // For each mu, we just find the minimum of J_obj over
  // the subset of vectors in SCM_UB_vectors corresponding
  // to C_J_M (SCM_UB_vectors contains vectors for all of
  // C_J).
  Real min_J_obj = 0.;
  for (unsigned int m=0; m<n_rows; m++)
    {
      const std::vector<Real> UB_vector = SCM_UB_vectors[m];
 
      Real J_obj = 0.;
      for (unsigned int q=0; q<rb_theta_expansion->get_n_A_terms(); q++)
        {
          J_obj += libmesh_real( rb_theta_expansion->eval_A_theta(q,get_parameters()) )*UB_vector[q];
        }
 
      if ((m==0) || (J_obj < min_J_obj))
        {
          min_J_obj = J_obj;
        }
    }
 
  return min_J_obj;
}
 
void RBSCMEvaluation::set_current_parameters_from_C_J(unsigned int C_J_index)
{
  set_parameters(C_J[C_J_index]);
}
 
void RBSCMEvaluation::save_current_parameters()
{
  saved_parameters = get_parameters();
}
 
void RBSCMEvaluation::reload_current_parameters()
{
  set_parameters(saved_parameters);
}
 
void RBSCMEvaluation::legacy_write_offline_data_to_files(const std::string & directory_name,
                                                         const bool write_binary_data)
{
  LOG_SCOPE("legacy_write_offline_data_to_files()", "RBSCMEvaluation");
 
  if (this->processor_id() == 0)
    {
      // Make a directory to store all the data files
      if (mkdir(directory_name.c_str(), 0777) == -1)
        {
          libMesh::out << "In RBSCMEvaluation::write_offline_data_to_files, directory "
                       << directory_name << " already exists, overwriting contents." << std::endl;
        }
 
      // The writing mode: ENCODE for binary, WRITE for ASCII
      XdrMODE mode = write_binary_data ? ENCODE : WRITE;
 
      // The suffix to use for all the files that are written out
      const std::string suffix = write_binary_data ? ".xdr" : ".dat";
 
      // Stream for building the file names
      std::ostringstream file_name;
 
      // Write out the parameter ranges
      file_name.str("");
      file_name << directory_name << "/parameter_ranges" << suffix;
      std::string continuous_param_file_name = file_name.str();
 
      // Write out the discrete parameter values
      file_name.str("");
      file_name << directory_name << "/discrete_parameter_values" << suffix;
      std::string discrete_param_file_name = file_name.str();
 
      write_parameter_data_to_files(continuous_param_file_name,
                                    discrete_param_file_name,
                                    write_binary_data);
 
      // Write out the bounding box min values
      file_name.str("");
      file_name << directory_name << "/B_min" << suffix;
      Xdr B_min_out(file_name.str(), mode);
 
      for (auto i : make_range(B_min.size()))
        {
          Real B_min_i = get_B_min(i);
          B_min_out << B_min_i;
        }
      B_min_out.close();
 
 
      // Write out the bounding box max values
      file_name.str("");
      file_name << directory_name << "/B_max" << suffix;
      Xdr B_max_out(file_name.str(), mode);
 
      for (auto i : make_range(B_max.size()))
        {
          Real B_max_i = get_B_max(i);
          B_max_out << B_max_i;
        }
      B_max_out.close();
 
      // Write out the length of the C_J data
      file_name.str("");
      file_name << directory_name << "/C_J_length" << suffix;
      Xdr C_J_length_out(file_name.str(), mode);
 
      unsigned int C_J_length = cast_int<unsigned int>(C_J.size());
      C_J_length_out << C_J_length;
      C_J_length_out.close();
 
      // Write out C_J_stability_vector
      file_name.str("");
      file_name << directory_name << "/C_J_stability_vector" << suffix;
      Xdr C_J_stability_vector_out(file_name.str(), mode);
 
      for (auto i : make_range(C_J_stability_vector.size()))
        {
          Real C_J_stability_constraint_i = get_C_J_stability_constraint(i);
          C_J_stability_vector_out << C_J_stability_constraint_i;
        }
      C_J_stability_vector_out.close();
 
      // Write out C_J
      file_name.str("");
      file_name << directory_name << "/C_J" << suffix;
      Xdr C_J_out(file_name.str(), mode);
 
      for (const auto & param : C_J)
        for (const auto & pr : param)
          for (const auto & value_vector : pr.second)
            {
              // Need to make a copy of the value so that it's not const
              // Xdr is not templated on const's
              libmesh_error_msg_if(value_vector.size() != 1,
                                   "Error: multi-value RB parameters are not yet supported here.");
              Real param_value = value_vector[0];
              C_J_out << param_value;
            }
      C_J_out.close();
 
      // Write out SCM_UB_vectors get_SCM_UB_vector
      file_name.str("");
      file_name << directory_name << "/SCM_UB_vectors" << suffix;
      Xdr SCM_UB_vectors_out(file_name.str(), mode);
 
      for (auto i : make_range(SCM_UB_vectors.size()))
        for (auto j : make_range(rb_theta_expansion->get_n_A_terms()))
          {
            Real SCM_UB_vector_ij = get_SCM_UB_vector(i,j);
            SCM_UB_vectors_out << SCM_UB_vector_ij;
          }
      SCM_UB_vectors_out.close();
    }
}
 
 
void RBSCMEvaluation::legacy_read_offline_data_from_files(const std::string & directory_name,
                                                          const bool read_binary_data)
{
  LOG_SCOPE("legacy_read_offline_data_from_files()", "RBSCMEvaluation");
 
  // The reading mode: DECODE for binary, READ for ASCII
  XdrMODE mode = read_binary_data ? DECODE : READ;
 
  // The suffix to use for all the files that are written out
  const std::string suffix = read_binary_data ? ".xdr" : ".dat";
 
  // The string stream we'll use to make the file names
  std::ostringstream file_name;
 
  // Read in the parameter ranges
  file_name.str("");
  file_name << directory_name << "/parameter_ranges" << suffix;
  std::string continuous_param_file_name = file_name.str();
 
  // Read in the discrete parameter values
  file_name.str("");
  file_name << directory_name << "/discrete_parameter_values" << suffix;
  std::string discrete_param_file_name = file_name.str();
  read_parameter_data_from_files(continuous_param_file_name,
                                 discrete_param_file_name,
                                 read_binary_data);
 
  // Read in the bounding box min values
  // Note that there are Q_a values
  file_name.str("");
  file_name << directory_name << "/B_min" << suffix;
  Xdr B_min_in(file_name.str(), mode);
 
  B_min.clear();
  for (unsigned int i=0; i<rb_theta_expansion->get_n_A_terms(); i++)
    {
      Real B_min_val;
      B_min_in >> B_min_val;
      B_min.push_back(B_min_val);
    }
  B_min_in.close();
 
 
  // Read in the bounding box max values
  // Note that there are Q_a values
  file_name.str("");
  file_name << directory_name << "/B_max" << suffix;
  Xdr B_max_in(file_name.str(), mode);
 
  B_max.clear();
  for (unsigned int i=0; i<rb_theta_expansion->get_n_A_terms(); i++)
    {
      Real B_max_val;
      B_max_in >> B_max_val;
      B_max.push_back(B_max_val);
    }
 
  // Read in the length of the C_J data
  file_name.str("");
  file_name << directory_name << "/C_J_length" << suffix;
  Xdr C_J_length_in(file_name.str(), mode);
 
  unsigned int C_J_length;
  C_J_length_in >> C_J_length;
  C_J_length_in.close();
 
  // Read in C_J_stability_vector
  file_name.str("");
  file_name << directory_name << "/C_J_stability_vector" << suffix;
  Xdr C_J_stability_vector_in(file_name.str(), mode);
 
  C_J_stability_vector.clear();
  for (unsigned int i=0; i<C_J_length; i++)
    {
      Real C_J_stability_val;
      C_J_stability_vector_in >> C_J_stability_val;
      C_J_stability_vector.push_back(C_J_stability_val);
    }
  C_J_stability_vector_in.close();
 
  // Read in C_J
  file_name.str("");
  file_name << directory_name << "/C_J" << suffix;
  Xdr C_J_in(file_name.str(), mode);
 
  // Resize C_J based on C_J_stability_vector and Q_a
  C_J.resize( C_J_length );
  for (auto & params : C_J)
    for (const auto & pr : get_parameters())
      {
        const std::string & param_name = pr.first;
        Real param_value;
        C_J_in >> param_value;
        params.set_value(param_name, param_value);
      }
  C_J_in.close();
 
 
  // Read in SCM_UB_vectors get_SCM_UB_vector
  file_name.str("");
  file_name << directory_name << "/SCM_UB_vectors" << suffix;
  Xdr SCM_UB_vectors_in(file_name.str(), mode);
 
  // Resize SCM_UB_vectors based on C_J_stability_vector and Q_a
  SCM_UB_vectors.resize( C_J_stability_vector.size() );
  for (auto i : index_range(SCM_UB_vectors))
    {
      SCM_UB_vectors[i].resize( rb_theta_expansion->get_n_A_terms() );
      for (unsigned int j=0; j<rb_theta_expansion->get_n_A_terms(); j++)
        {
          SCM_UB_vectors_in >> SCM_UB_vectors[i][j];
        }
    }
  SCM_UB_vectors_in.close();
}
 
} // namespace libMesh
 
#endif // LIBMESH_HAVE_SLEPC && LIBMESH_HAVE_GLPK