LinearCombination.cc

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/*
 * $Id: LinearCombination.cc 177 2013-07-02 16:59:05Z jdl3 $
 * Copyright (C) 2013 John D Lamb
 *
 * This program 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 2 of the License, or (at
 * your option) any later version.
 * 
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifdef HAVE_CONFIG_H
#  include<config.h>
#endif

#include"LinearCombination.hpp"

using namespace ipo_function::concrete;

LinearCombination::LinearCombination( size_t const size )
  : FunctionBase { size }, coefficients( size ){ coefficients.set_all( 0.0 ); }

void
LinearCombination::resize( size_t const size ){
  if( coefficients.size() != size ){
    size_t const MIN { std::min( size, coefficients.size() ) };
    auto oldCoefficients = coefficients;
    coefficients = gsl::vector( size );
    // copy old values
    for( size_t index { 0 }; index < MIN; ++index )
      coefficients[index] = oldCoefficients[index];
    // zero new values
    for( size_t index { MIN }; index < coefficients.size(); ++index )
      coefficients[index] = 0;
  }
}

void
LinearCombination::setCoefficient( size_t const index, double const value ){
  if( index > coefficients.size() ){
    using namespace ipo;
    throw IPOE( "ipo_function::concrete::LinearCombination::setCoefficient(): "
        "index out of range." );
  }
  coefficients[index] = value;
}

double
LinearCombination::getCoefficient( size_t const index ) const {
  if( index > coefficients.size() ){
    using namespace ipo;
    throw IPOE( "ipo_function::concrete::LinearCombination::getCoefficient(): "
        "index out of range." );
  }
  return coefficients[index];
}

gsl::vector const&
LinearCombination::getCoefficients() const {
  return coefficients;
}

void
LinearCombination::setCoefficients( gsl::vector const& vector ){
  if( vector.size() != coefficients.size() ){
    using namespace ipo;
    std::ostringstream
      ost { "ipo_function::concrete::LinearCombination::setCoefficients(): " };
    ost << "vector size " << vector.size();
    ost << " and coefficients size " << coefficients.size();
    ost << " do not match.";
    throw IPOE( ost.str() );
  }
  coefficients.memcpy( vector );
}

double
LinearCombination::operator()( gsl::vector const& vector ){
  if( vector.size() != coefficients.size() ){
    using namespace ipo;
    std::ostringstream ost { "ipo_function::concrete::LinearCombination::operator()(): " };
    ost << "vector size " << vector.size();
    ost << " and coefficients size " << coefficients.size();
    ost << " do not match.";
    throw IPOE( ost.str() );
  }
  double result { 0.0 };
  gsl::blas::ddot( coefficients, vector, &result ); 
  return result;
}

gsl::vector
LinearCombination::gradient( gsl::vector const& vector ){
  size_t const SIZE { vector.size() };
  if( SIZE != coefficients.size() ){
    using namespace ipo;
    std::ostringstream ost { "ipo_function::concrete::LinearCombination::gradient(): " };
    ost << "vector size " << vector.size();
    ost << " and coefficients size " << coefficients.size();
    ost << " do not match.";
    throw IPOE( ost.str() );
  }
  // return a copy of coefficients
  if( functionGradient.size() != SIZE )
    functionGradient = gsl::vector( SIZE );
  functionGradient.memcpy( coefficients );
  return functionGradient;
}

gsl::matrix
LinearCombination::hessian( gsl::vector const& vector ){
  size_t const SIZE { vector.size() };
  if( SIZE != coefficients.size() ){
    using namespace ipo;
    std::ostringstream ost { "ipo_function::concrete::LinearCombination::hessian(): " };
    ost << "vector size " << vector.size();
    ost << " and coefficients size " << coefficients.size();
    ost << " do not match.";
    throw IPOE( ost.str() );
  }
  if( functionHessian.size1() != SIZE or functionHessian.size2() != SIZE )
    functionHessian = gsl::matrix { SIZE, SIZE };
  functionHessian.set_all( 0.0 );
  return functionHessian;
}

void
LinearCombination::setVector( gsl::vector const& vector ){
  size_t const SIZE { vector.size() };
  if( SIZE != coefficients.size() ){
    using namespace ipo;
    std::ostringstream ost { "ipo_function::concrete::LinearCombination::setVector(): " };
    ost << "vector size " << vector.size();
    ost << " and coefficients size " << coefficients.size();
    ost << " do not match.";
    throw IPOE( ost.str() );
  }
  gsl::blas::ddot( coefficients, vector, &functionValue ); 
  if( functionGradient.size() != SIZE )
    functionGradient = gsl::vector( SIZE );
  functionGradient.memcpy( coefficients );
  if( functionHessian.size1() != SIZE or functionHessian.size2() != SIZE )
    functionHessian = gsl::matrix( SIZE, SIZE );
  functionHessian.set_all( 0 );
}