vector_expression.hpp

support vector clustering for vc++

                if (it1_ != it1_end_)
                    if (it1_.index () <= i_)
                        ++ it1_;
                if (it2_ != it2_end_)
                    if (it2_.index () <= i_)
                        ++ it2_;
                ++ i_;
            }
            BOOST_UBLAS_INLINE
            void decrement (packed_random_access_iterator_tag) {
                if (it1_ != it1_end_)
                    if (i_ <= it1_.index ())
                        -- it1_;
                if (it2_ != it2_end_)
                    if (i_ <= it2_.index ())
                        -- it2_;
                -- i_;
            }
            BOOST_UBLAS_INLINE
            void increment (packed_random_access_iterator_tag, difference_type n) {
                while (n > 0) {
                    increment (packed_random_access_iterator_tag ());
                    --n;
                }
                while (n < 0) {
                    decrement (packed_random_access_iterator_tag ());
                    ++n;
                }
            }
            BOOST_UBLAS_INLINE
            void decrement (packed_random_access_iterator_tag, difference_type n) {
                while (n > 0) {
                    decrement (packed_random_access_iterator_tag ());
                    --n;
                }
                while (n < 0) {
                    increment (packed_random_access_iterator_tag ());
                    ++n;
                }
            }
            BOOST_UBLAS_INLINE
            value_type dereference (packed_random_access_iterator_tag) const {
                value_type t1 = value_type/*zero*/();
                if (it1_ != it1_end_)
                    if (it1_.index () == i_)
                        t1 = *it1_;
                value_type t2 = value_type/*zero*/();
                if (it2_ != it2_end_)
                    if (it2_.index () == i_)
                        t2 = *it2_;
                return functor_type::apply (t1, t2);
            }

            // Sparse specializations
            BOOST_UBLAS_INLINE
            void increment (sparse_bidirectional_iterator_tag) {
                size_type index1 = (*this) ().size ();
                if (it1_ != it1_end_) {
                    if  (it1_.index () <= i_)
                        ++ it1_;
                    if (it1_ != it1_end_)
                        index1 = it1_.index ();
                }
                size_type index2 = (*this) ().size ();
                if (it2_ != it2_end_) {
                    if (it2_.index () <= i_)
                        ++ it2_;
                    if (it2_ != it2_end_)
                        index2 = it2_.index ();
                }
                i_ = (std::min) (index1, index2);
            }
            BOOST_UBLAS_INLINE
            void decrement (sparse_bidirectional_iterator_tag) {
                size_type index1 = (*this) ().size ();
                if (it1_ != it1_end_) {
                    if (i_ <= it1_.index ())
                        -- it1_;
                    if (it1_ != it1_end_)
                        index1 = it1_.index ();
                }
                size_type index2 = (*this) ().size ();
                if (it2_ != it2_end_) {
                    if (i_ <= it2_.index ())
                        -- it2_;
                    if (it2_ != it2_end_)
                        index2 = it2_.index ();
                }
                i_ = (std::max) (index1, index2);
            }
            BOOST_UBLAS_INLINE
            void increment (sparse_bidirectional_iterator_tag, difference_type n) {
                while (n > 0) {
                    increment (sparse_bidirectional_iterator_tag ());
                    --n;
                }
                while (n < 0) {
                    decrement (sparse_bidirectional_iterator_tag ());
                    ++n;
                }
            }
            BOOST_UBLAS_INLINE
            void decrement (sparse_bidirectional_iterator_tag, difference_type n) {
                while (n > 0) {
                    decrement (sparse_bidirectional_iterator_tag ());
                    --n;
                }
                while (n < 0) {
                    increment (sparse_bidirectional_iterator_tag ());
                    ++n;
                }
            }
            BOOST_UBLAS_INLINE
            value_type dereference (sparse_bidirectional_iterator_tag) const {
                value_type t1 = value_type/*zero*/();
                if (it1_ != it1_end_)
                    if (it1_.index () == i_)
                        t1 = *it1_;
                value_type t2 = value_type/*zero*/();
                if (it2_ != it2_end_)
                    if (it2_.index () == i_)
                        t2 = *it2_;
                return functor_type::apply (t1, t2);
            }

        public: 
            // Arithmetic
            BOOST_UBLAS_INLINE
            const_iterator &operator ++ () {
                increment (iterator_category ());
                return *this;
            }
            BOOST_UBLAS_INLINE
            const_iterator &operator -- () {
                decrement (iterator_category ());
                return *this;
            }
            BOOST_UBLAS_INLINE
            const_iterator &operator += (difference_type n) {
                increment (iterator_category (), n);
                return *this;
            }
            BOOST_UBLAS_INLINE
            const_iterator &operator -= (difference_type n) {
                decrement (iterator_category (), n);
                return *this;
            }
            BOOST_UBLAS_INLINE
            difference_type operator - (const const_iterator &it) const {
                BOOST_UBLAS_CHECK ((*this) ().same_closure (it ()), external_logic ());
                return index () - it.index ();
            }

            // Dereference
            BOOST_UBLAS_INLINE
            const_reference operator * () const {
                return dereference (iterator_category ());
            }
            BOOST_UBLAS_INLINE
            const_reference operator [] (difference_type n) const {
                return *(*this + n);
            }

            // Index
            BOOST_UBLAS_INLINE
            size_type index () const {
                return i_;
            }

            // Assignment
            BOOST_UBLAS_INLINE
            const_iterator &operator = (const const_iterator &it) {
                container_const_reference<self_type>::assign (&it ());
                i_ = it.i_;
                it1_ = it.it1_;
                it1_end_ = it.it1_end_;
                it2_ = it.it2_;
                it2_end_ = it.it2_end_;
                return *this;
            }

            // Comparison
            BOOST_UBLAS_INLINE
            bool operator == (const const_iterator &it) const {
                BOOST_UBLAS_CHECK ((*this) ().same_closure (it ()), external_logic ());
                return index () == it.index ();
            }
            BOOST_UBLAS_INLINE
            bool operator < (const const_iterator &it) const {
                BOOST_UBLAS_CHECK ((*this) ().same_closure (it ()), external_logic ());
                return index () < it.index ();
            }

        private:
            size_type i_;
            const_subiterator1_type it1_;
            const_subiterator1_type it1_end_;
            const_subiterator2_type it2_;
            const_subiterator2_type it2_end_;
        };
#endif

        BOOST_UBLAS_INLINE
        const_iterator begin () const {
            return find (0);
        }
        BOOST_UBLAS_INLINE
        const_iterator end () const {
            return find (size ());
        }

        // Reverse iterator
        typedef reverse_iterator_base<const_iterator> const_reverse_iterator;

        BOOST_UBLAS_INLINE
        const_reverse_iterator rbegin () const {
            return const_reverse_iterator (end ());
        }
        BOOST_UBLAS_INLINE
        const_reverse_iterator rend () const {
            return const_reverse_iterator (begin ());
        }

    private:
        expression1_closure_type e1_;
        expression2_closure_type e2_;
    };

    template<class E1, class E2, class F>
    struct vector_binary_traits {
        typedef vector_binary<E1, E2, F> expression_type;
#ifndef BOOST_UBLAS_SIMPLE_ET_DEBUG
        typedef expression_type result_type; 
#else
        typedef typename E1::vector_temporary_type result_type;
#endif
    };

    // (v1 + v2) [i] = v1 [i] + v2 [i]
    template<class E1, class E2>
    BOOST_UBLAS_INLINE
    typename vector_binary_traits<E1, E2, scalar_plus<typename E1::value_type, 
                                                      typename E2::value_type> >::result_type
    operator + (const vector_expression<E1> &e1,
                const vector_expression<E2> &e2) {
        typedef typename vector_binary_traits<E1, E2, scalar_plus<typename E1::value_type,
                                                                              typename E2::value_type> >::expression_type expression_type;
        return expression_type (e1 (), e2 ());
    }

    // (v1 - v2) [i] = v1 [i] - v2 [i]
    template<class E1, class E2>
    BOOST_UBLAS_INLINE
    typename vector_binary_traits<E1, E2, scalar_minus<typename E1::value_type,
                                                       typename E2::value_type> >::result_type
    operator - (const vector_expression<E1> &e1,
                const vector_expression<E2> &e2) {
        typedef typename vector_binary_traits<E1, E2, scalar_minus<typename E1::value_type,
                                                                               typename E2::value_type> >::expression_type expression_type;
        return expression_type (e1 (), e2 ());
    }

    // (v1 * v2) [i] = v1 [i] * v2 [i]
    template<class E1, class E2>
    BOOST_UBLAS_INLINE
    typename vector_binary_traits<E1, E2, scalar_multiplies<typename E1::value_type,
                                                            typename E2::value_type> >::result_type
    element_prod (const vector_expression<E1> &e1,
                  const vector_expression<E2> &e2) {
        typedef typename vector_binary_traits<E1, E2, scalar_multiplies<typename E1::value_type,
                                                                                    typename E2::value_type> >::expression_type expression_type;
        return expression_type (e1 (), e2 ());
    }

    // (v1 / v2) [i] = v1 [i] / v2 [i]
    template<class E1, class E2>
    BOOST_UBLAS_INLINE
    typename vector_binary_traits<E1, E2, scalar_divides<typename E1::value_type,
                                                         typename E2::value_type> >::result_type
    element_div (const vector_expression<E1> &e1,
                 const vector_expression<E2> &e2) {
        typedef typename vector_binary_traits<E1, E2, scalar_divides<typename E1::value_type,
                                                                                 typename E2::value_type> >::expression_type expression_type;
        return expression_type (e1 (), e2 ());
    }


    template<class E1, class E2, class F>
    class vector_binary_scalar1:
        public vector_expression<vector_binary_scalar1<E1, E2, F> > {

        typedef F functor_type;
        typedef E1 expression1_type;
        typedef E2 expression2_type;
    public:
        typedef const E1& expression1_closure_type;
        typedef typename E2::const_closure_type expression2_closure_type;
    private:
        typedef vector_binary_scalar1<E1, E2, F> self_type;
    public:
#ifdef BOOST_UBLAS_ENABLE_PROXY_SHORTCUTS
        using vector_expression<vector_binary_scalar1<E1, E2, F> >::operator ();
#endif
        typedef typename E2::size_type size_type;
        typedef typename E2::difference_type difference_type;
        typedef typename F::result_type value_type;
        typedef value_type const_reference;
        typedef const_reference reference;
        typedef const self_type const_closure_type;
        typedef const_closure_type closure_type;
        typedef unknown_storage_tag storage_category;

        // Construction and destruction
        BOOST_UBLAS_INLINE
        vector_binary_scalar1 (const expression1_type &e1, const expression2_type &e2):
            e1_ (e1), e2_ (e2) {}

        // Accessors
        BOOST_UBLAS_INLINE
        size_type size () const {
            return e2_.size ();
        }

    public:
        // Element access
        BOOST_UBLAS_INLINE
        const_reference operator () (size_type i) const {
            return functor_type::apply (e1_, e2_ (i));
        }

        BOOST_UBLAS_INLINE
        const_reference operator [] (size_type i) const {
            return functor_type::apply (e1_, e2_ [i]);
        }