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diff --git a/include/2geom/numeric/fitting-tool.h b/include/2geom/numeric/fitting-tool.h new file mode 100644 index 0000000..78d66ca --- /dev/null +++ b/include/2geom/numeric/fitting-tool.h @@ -0,0 +1,562 @@ +/* + * Fitting Tools + * + * Authors: + * Marco Cecchetti <mrcekets at gmail.com> + * + * Copyright 2008 authors + * + * This library is free software; you can redistribute it and/or + * modify it either under the terms of the GNU Lesser General Public + * License version 2.1 as published by the Free Software Foundation + * (the "LGPL") or, at your option, under the terms of the Mozilla + * Public License Version 1.1 (the "MPL"). If you do not alter this + * notice, a recipient may use your version of this file under either + * the MPL or the LGPL. + * + * You should have received a copy of the LGPL along with this library + * in the file COPYING-LGPL-2.1; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * You should have received a copy of the MPL along with this library + * in the file COPYING-MPL-1.1 + * + * The contents of this file are subject to the Mozilla Public License + * Version 1.1 (the "License"); you may not use this file except in + * compliance with the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY + * OF ANY KIND, either express or implied. See the LGPL or the MPL for + * the specific language governing rights and limitations. + */ + + +#ifndef _NL_FITTING_TOOL_H_ +#define _NL_FITTING_TOOL_H_ + + +#include <2geom/numeric/vector.h> +#include <2geom/numeric/matrix.h> + +#include <2geom/point.h> + +#include <vector> + + +/* + * The least_square_fitter class represents a tool for solving a fitting + * problem with respect to a given model that represents an expression + * dependent from a parameter where the coefficients of this expression + * are the unknowns of the fitting problem. + * The minimizing solution is found by computing the pseudo-inverse + * of the problem matrix + */ + + +namespace Geom { namespace NL { + +namespace detail { + +template< typename ModelT> +class lsf_base +{ + public: + typedef ModelT model_type; + typedef typename model_type::parameter_type parameter_type; + typedef typename model_type::value_type value_type; + + lsf_base( model_type const& _model, size_t forecasted_samples ) + : m_model(_model), + m_total_samples(0), + m_matrix(forecasted_samples, m_model.size()), + m_psdinv_matrix(NULL) + { + } + + // compute pseudo inverse + void update() + { + if (total_samples() == 0) return; + if (m_psdinv_matrix != NULL) + { + delete m_psdinv_matrix; + } + MatrixView mv(m_matrix, 0, 0, total_samples(), m_matrix.columns()); + m_psdinv_matrix = new Matrix( pseudo_inverse(mv) ); + assert(m_psdinv_matrix != NULL); + } + + size_t total_samples() const + { + return m_total_samples; + } + + bool is_full() const + { + return (total_samples() == m_matrix.rows()); + } + + void clear() + { + m_total_samples = 0; + } + + virtual + ~lsf_base() + { + if (m_psdinv_matrix != NULL) + { + delete m_psdinv_matrix; + } + } + + protected: + const model_type & m_model; + size_t m_total_samples; + Matrix m_matrix; + Matrix* m_psdinv_matrix; + +}; // end class lsf_base + + + + +template< typename ModelT, typename ValueType = typename ModelT::value_type> +class lsf_solution +{ +}; + +// a fitting process on samples with value of type double +// produces a solution of type Vector +template< typename ModelT> +class lsf_solution<ModelT, double> + : public lsf_base<ModelT> +{ +public: + typedef ModelT model_type; + typedef typename model_type::parameter_type parameter_type; + typedef typename model_type::value_type value_type; + typedef Vector solution_type; + typedef lsf_base<model_type> base_type; + + using base_type::m_model; + using base_type::m_psdinv_matrix; + using base_type::total_samples; + +public: + lsf_solution<ModelT, double>( model_type const& _model, + size_t forecasted_samples ) + : base_type(_model, forecasted_samples), + m_solution(_model.size()) + { + } + + template< typename VectorT > + solution_type& result(VectorT const& sample_values) + { + assert(sample_values.size() == total_samples()); + ConstVectorView sv(sample_values); + m_solution = (*m_psdinv_matrix) * sv; + return m_solution; + } + + // a comparison between old sample values and the new ones is performed + // in order to minimize computation + // prerequisite: + // old_sample_values.size() == new_sample_values.size() + // no update() call can be performed between two result invocations + template< typename VectorT > + solution_type& result( VectorT const& old_sample_values, + VectorT const& new_sample_values ) + { + assert(old_sample_values.size() == total_samples()); + assert(new_sample_values.size() == total_samples()); + Vector diff(total_samples()); + for (size_t i = 0; i < diff.size(); ++i) + { + diff[i] = new_sample_values[i] - old_sample_values[i]; + } + Vector column(m_model.size()); + Vector delta(m_model.size(), 0.0); + for (size_t i = 0; i < diff.size(); ++i) + { + if (diff[i] != 0) + { + column = m_psdinv_matrix->column_view(i); + column.scale(diff[i]); + delta += column; + } + } + m_solution += delta; + return m_solution; + } + + solution_type& result() + { + return m_solution; + } + +private: + solution_type m_solution; + +}; // end class lsf_solution<ModelT, double> + + +// a fitting process on samples with value of type Point +// produces a solution of type Matrix (with 2 columns) +template< typename ModelT> +class lsf_solution<ModelT, Point> + : public lsf_base<ModelT> +{ +public: + typedef ModelT model_type; + typedef typename model_type::parameter_type parameter_type; + typedef typename model_type::value_type value_type; + typedef Matrix solution_type; + typedef lsf_base<model_type> base_type; + + using base_type::m_model; + using base_type::m_psdinv_matrix; + using base_type::total_samples; + +public: + lsf_solution<ModelT, Point>( model_type const& _model, + size_t forecasted_samples ) + : base_type(_model, forecasted_samples), + m_solution(_model.size(), 2) + { + } + + solution_type& result(std::vector<Point> const& sample_values) + { + assert(sample_values.size() == total_samples()); + Matrix svm(total_samples(), 2); + for (size_t i = 0; i < total_samples(); ++i) + { + svm(i, X) = sample_values[i][X]; + svm(i, Y) = sample_values[i][Y]; + } + m_solution = (*m_psdinv_matrix) * svm; + return m_solution; + } + + // a comparison between old sample values and the new ones is performed + // in order to minimize computation + // prerequisite: + // old_sample_values.size() == new_sample_values.size() + // no update() call can to be performed between two result invocations + solution_type& result( std::vector<Point> const& old_sample_values, + std::vector<Point> const& new_sample_values ) + { + assert(old_sample_values.size() == total_samples()); + assert(new_sample_values.size() == total_samples()); + Matrix diff(total_samples(), 2); + for (size_t i = 0; i < total_samples(); ++i) + { + diff(i, X) = new_sample_values[i][X] - old_sample_values[i][X]; + diff(i, Y) = new_sample_values[i][Y] - old_sample_values[i][Y]; + } + Vector column(m_model.size()); + Matrix delta(m_model.size(), 2, 0.0); + VectorView deltax = delta.column_view(X); + VectorView deltay = delta.column_view(Y); + for (size_t i = 0; i < total_samples(); ++i) + { + if (diff(i, X) != 0) + { + column = m_psdinv_matrix->column_view(i); + column.scale(diff(i, X)); + deltax += column; + } + if (diff(i, Y) != 0) + { + column = m_psdinv_matrix->column_view(i); + column.scale(diff(i, Y)); + deltay += column; + } + } + m_solution += delta; + return m_solution; + } + + solution_type& result() + { + return m_solution; + } + +private: + solution_type m_solution; + +}; // end class lsf_solution<ModelT, Point> + + + + +template< typename ModelT, + bool WITH_FIXED_TERMS = ModelT::WITH_FIXED_TERMS > +class lsf_with_fixed_terms +{ +}; + + +// fitting tool for completely unknown models +template< typename ModelT> +class lsf_with_fixed_terms<ModelT, false> + : public lsf_solution<ModelT> +{ + public: + typedef ModelT model_type; + typedef typename model_type::parameter_type parameter_type; + typedef typename model_type::value_type value_type; + typedef lsf_solution<model_type> base_type; + typedef typename base_type::solution_type solution_type; + + using base_type::total_samples; + using base_type::is_full; + using base_type::m_matrix; + using base_type::m_total_samples; + using base_type::m_model; + + public: + lsf_with_fixed_terms<ModelT, false>( model_type const& _model, + size_t forecasted_samples ) + : base_type(_model, forecasted_samples) + { + } + + void append(parameter_type const& sample_parameter) + { + assert(!is_full()); + VectorView row = m_matrix.row_view(total_samples()); + m_model.feed(row, sample_parameter); + ++m_total_samples; + } + + void append_copy(size_t sample_index) + { + assert(!is_full()); + assert(sample_index < total_samples()); + VectorView dest_row = m_matrix.row_view(total_samples()); + VectorView source_row = m_matrix.row_view(sample_index); + dest_row = source_row; + ++m_total_samples; + } + +}; // end class lsf_with_fixed_terms<ModelT, false> + + +// fitting tool for partially known models +template< typename ModelT> +class lsf_with_fixed_terms<ModelT, true> + : public lsf_solution<ModelT> +{ + public: + typedef ModelT model_type; + typedef typename model_type::parameter_type parameter_type; + typedef typename model_type::value_type value_type; + typedef lsf_solution<model_type> base_type; + typedef typename base_type::solution_type solution_type; + + using base_type::total_samples; + using base_type::is_full; + using base_type::m_matrix; + using base_type::m_total_samples; + using base_type::m_model; + + public: + lsf_with_fixed_terms<ModelT, true>( model_type const& _model, + size_t forecasted_samples ) + : base_type(_model, forecasted_samples), + m_vector(forecasted_samples), + m_vector_view(NULL) + { + } + void append(parameter_type const& sample_parameter) + { + assert(!is_full()); + VectorView row = m_matrix.row_view(total_samples()); + m_model.feed(row, m_vector[total_samples()], sample_parameter); + ++m_total_samples; + } + + void append_copy(size_t sample_index) + { + assert(!is_full()); + assert(sample_index < total_samples()); + VectorView dest_row = m_matrix.row_view(total_samples()); + VectorView source_row = m_matrix.row_view(sample_index); + dest_row = source_row; + m_vector[total_samples()] = m_vector[sample_index]; + ++m_total_samples; + } + + void update() + { + base_type::update(); + if (total_samples() == 0) return; + if (m_vector_view != NULL) + { + delete m_vector_view; + } + m_vector_view = new VectorView(m_vector, base_type::total_samples()); + assert(m_vector_view != NULL); + } + + + ~lsf_with_fixed_terms<model_type, true>() override + { + if (m_vector_view != NULL) + { + delete m_vector_view; + } + } + + protected: + Vector m_vector; + VectorView* m_vector_view; + +}; // end class lsf_with_fixed_terms<ModelT, true> + + +} // end namespace detail + + + + +template< typename ModelT, + typename ValueType = typename ModelT::value_type, + bool WITH_FIXED_TERMS = ModelT::WITH_FIXED_TERMS > +class least_squeares_fitter +{ +}; + + +template< typename ModelT, typename ValueType > +class least_squeares_fitter<ModelT, ValueType, false> + : public detail::lsf_with_fixed_terms<ModelT> +{ + public: + typedef ModelT model_type; + typedef detail::lsf_with_fixed_terms<model_type> base_type; + typedef typename base_type::parameter_type parameter_type; + typedef typename base_type::value_type value_type; + typedef typename base_type::solution_type solution_type; + + public: + least_squeares_fitter<ModelT, ValueType, false>( model_type const& _model, + size_t forecasted_samples ) + : base_type(_model, forecasted_samples) + { + } +}; // end class least_squeares_fitter<ModelT, ValueType, true> + + +template< typename ModelT> +class least_squeares_fitter<ModelT, double, true> + : public detail::lsf_with_fixed_terms<ModelT> +{ + public: + typedef ModelT model_type; + typedef detail::lsf_with_fixed_terms<model_type> base_type; + typedef typename base_type::parameter_type parameter_type; + typedef typename base_type::value_type value_type; + typedef typename base_type::solution_type solution_type; + + using base_type::m_vector_view; + //using base_type::result; // VSC legacy support + solution_type& result( std::vector<Point> const& old_sample_values, + std::vector<Point> const& new_sample_values ) + { + return base_type::result(old_sample_values, new_sample_values); + } + + solution_type& result() + { + return base_type::result(); + } + + public: + least_squeares_fitter<ModelT, double, true>( model_type const& _model, + size_t forecasted_samples ) + : base_type(_model, forecasted_samples) + { + } + + template< typename VectorT > + solution_type& result(VectorT const& sample_values) + { + assert(sample_values.size() == m_vector_view->size()); + Vector sv(sample_values.size()); + for (size_t i = 0; i < sv.size(); ++i) + sv[i] = sample_values[i] - (*m_vector_view)[i]; + return base_type::result(sv); + } + +}; // end class least_squeares_fitter<ModelT, double, true> + + +template< typename ModelT> +class least_squeares_fitter<ModelT, Point, true> + : public detail::lsf_with_fixed_terms<ModelT> +{ + public: + typedef ModelT model_type; + typedef detail::lsf_with_fixed_terms<model_type> base_type; + typedef typename base_type::parameter_type parameter_type; + typedef typename base_type::value_type value_type; + typedef typename base_type::solution_type solution_type; + + using base_type::m_vector_view; + //using base_type::result; // VCS legacy support + solution_type& result( std::vector<Point> const& old_sample_values, + std::vector<Point> const& new_sample_values ) + { + return base_type::result(old_sample_values, new_sample_values); + } + + solution_type& result() + { + return base_type::result(); + } + + + public: + least_squeares_fitter<ModelT, Point, true>( model_type const& _model, + size_t forecasted_samples ) + : base_type(_model, forecasted_samples) + { + } + + solution_type& result(std::vector<Point> const& sample_values) + { + assert(sample_values.size() == m_vector_view->size()); + NL::Matrix sv(sample_values.size(), 2); + for (size_t i = 0; i < sample_values.size(); ++i) + { + sv(i, X) = sample_values[i][X] - (*m_vector_view)[i]; + sv(i, Y) = sample_values[i][Y] - (*m_vector_view)[i]; + } + return base_type::result(sv); + } + +}; // end class least_squeares_fitter<ModelT, Point, true> + + +} // end namespace NL +} // end namespace Geom + + + +#endif // _NL_FITTING_TOOL_H_ + + +/* + Local Variables: + mode:c++ + c-file-style:"stroustrup" + c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) + indent-tabs-mode:nil + fill-column:99 + End: +*/ +// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 : |