vector_expression.hpp

boost库提供标准的C++ API 配合dev c++使用,功能更加强大

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

        private:
            size_type i_;
            const_iterator1_type it1_;
            const_iterator1_type it1_end_;
            const_iterator2_type it2_;
            const_iterator2_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

#ifdef BOOST_MSVC_STD_ITERATOR
        typedef reverse_iterator_base<const_iterator, value_type, const_reference> const_reverse_iterator;
#else
        typedef reverse_iterator_base<const_iterator> const_reverse_iterator;
#endif

        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;
#ifdef BOOST_UBLAS_USE_ET
        typedef expression_type result_type; 
#else
        typedef vector<typename F::result_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 BOOST_UBLAS_TYPENAME vector_binary_traits<E1, E2, scalar_plus<BOOST_UBLAS_TYPENAME E1::value_type,
                                                                              BOOST_UBLAS_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 BOOST_UBLAS_TYPENAME vector_binary_traits<E1, E2, scalar_minus<BOOST_UBLAS_TYPENAME E1::value_type,
                                                                               BOOST_UBLAS_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 BOOST_UBLAS_TYPENAME vector_binary_traits<E1, E2, scalar_multiplies<BOOST_UBLAS_TYPENAME E1::value_type,
                                                                                    BOOST_UBLAS_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 BOOST_UBLAS_TYPENAME vector_binary_traits<E1, E2, scalar_divides<BOOST_UBLAS_TYPENAME E1::value_type,
                                                                                 BOOST_UBLAS_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> > {
    public:
#ifndef BOOST_UBLAS_NO_PROXY_SHORTCUTS
        BOOST_UBLAS_USING vector_expression<vector_binary_scalar1<E1, E2, F> >::operator ();
#endif
        typedef E1 expression1_type;
        typedef E2 expression2_type;
        typedef F functor_type;
        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 value_type *const_pointer;
        typedef const_pointer pointer;
        typedef E1 expression1_closure_type;
        typedef typename E2::const_closure_type expression2_closure_type;
        typedef const vector_binary_scalar1<E1, E2, F> const_self_type;
        typedef vector_binary_scalar1<E1, E2, F> self_type;
        typedef const_self_type const_closure_type;
        typedef const_closure_type closure_type;
        typedef typename E1::value_type const_iterator1_type;
        typedef typename E2::const_iterator const_iterator2_type;
        typedef unknown_storage_tag storage_category;

        // Construction and destruction
        BOOST_UBLAS_INLINE
        vector_binary_scalar1 ():
            e1_ (), e2_ () {}
        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 ();
        }
        BOOST_UBLAS_INLINE
        const expression1_closure_type &expression1 () const {
            return e1_;
        }
        BOOST_UBLAS_INLINE
        const expression2_closure_type &expression2 () const {
            return e2_;
        }

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

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

#ifdef BOOST_UBLAS_USE_INDEXED_ITERATOR
        typedef indexed_const_iterator<const_closure_type, typename const_iterator2_type::iterator_category> const_iterator;
        typedef const_iterator iterator;
#else
        class const_iterator;
        typedef const_iterator iterator;
#endif

        // Element lookup
        BOOST_UBLAS_INLINE
        const_iterator find (size_type i) const {
#ifdef BOOST_UBLAS_USE_INDEXED_ITERATOR
            const_iterator2_type it (e2_.find (i));
            return const_iterator (*this, it.index ());
#else
            return const_iterator (*this, e1_, e2_.find (i));
#endif
        }

        // Iterator enhances the iterator of the referenced vector expression
        // with the binary functor.

#ifndef BOOST_UBLAS_USE_INDEXED_ITERATOR
        class const_iterator:
            public container_const_reference<vector_binary_scalar1>,
#ifdef BOOST_UBLAS_USE_ITERATOR_BASE_TRAITS
            public iterator_base_traits<typename E2::const_iterator::iterator_category>::template
                        iterator_base<const_iterator, value_type>::type {
#else
            public random_access_iterator_base<typename E2::const_iterator::iterator_category,
                                               const_iterator, value_type> {
#endif                                               
        public:
            typedef typename E2::const_iterator::iterator_category iterator_category;
#ifdef BOOST_MSVC_STD_ITERATOR
            typedef const_reference reference;
#else
            typedef typename vector_binary_scalar1::difference_type difference_type;
            typedef typename vector_binary_scalar1::value_type value_type;
            typedef typename vector_binary_scalar1::const_reference reference;
            typedef typename vector_binary_scalar1::const_pointer pointer;
#endif

            // Construction and destruction
            BOOST_UBLAS_INLINE
            const_iterator ():
                container_const_reference<self_type> (), it1_ (), it2_ () {}
            BOOST_UBLAS_INLINE
            const_iterator (const self_type &vbs, const const_iterator1_type &it1, const const_iterator2_type &it2):
                container_const_reference<self_type> (vbs), it1_ (it1), it2_ (it2) {}

            // Arithmetic
            BOOST_UBLAS_INLINE
            const_iterator &operator ++ () {
                ++ it2_;
                return *this;
            }
            BOOST_UBLAS_INLINE
            const_iterator &operator -- () {
                -- it2_;
                return *this;
            }
            BOOST_UBLAS_INLINE
            const_iterator &operator += (difference_type n) {
                it2_ += n;
                return *this;
            }
            BOOST_UBLAS_INLINE
            const_iterator &operator -= (difference_type n) {
                it2_ -= n;
                return *this;
            }
            BOOST_UBLAS_INLINE
            difference_type operator - (const const_iterator &it) const {
                BOOST_UBLAS_CHECK (&(*this) () == &it (), external_logic ());
                // FIXME: we shouldn't compare floats
                // BOOST_UBLAS_CHECK (it1_ == it.it1_, external_logic ());
                return it2_ - it.it2_;
            }

            // Dereference
            BOOST_UBLAS_INLINE
            reference operator * () const {
                return functor_type () (it1_, *it2_);
            }

            // Index
            BOOST_UBLAS_INLINE
            size_type index () const {
                return it2_.index ();
            }

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

            // Comparison
            BOOST_UBLAS_INLINE
            bool operator == (const const_iterator &it) const {
                BOOST_UBLAS_CHECK (&(*this) () == &it (), external_logic ());
                // FIXME: we shouldn't compare floats
                // BOOST_UBLAS_CHECK (it1_ == it.it1_, external_logic ());
                return it2_ == it.it2_;
            }
            BOOST_UBLAS_INLINE
            bool operator < (const const_iterator &it) const {
                BOOST_UBLAS_CHECK (&(*this) () == &it (), external_logic ());
                // FIXME: we shouldn't compare floats
                // BOOST_UBLAS_CHECK (it1_ == it.it1_, external_logic ());
                return it2_ < it.it2_;
            }

        private:
            const_iterator1_type it1_;
            const_iterator2_type it2_;
        };
#endif

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

        // Reverse iterator

#ifdef BOOST_MSVC_STD_ITERATOR
        typedef reverse_iterator_base<const_iterator, value_type, const_reference> const_reverse_iterator;
#else
        typedef reverse_iterator_base<const_iterator> const_reverse_iterator;
#endif

        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 T1, class E2, class F>
    struct vector_binary_scalar1_traits {
        typedef vector_binary_scalar1<scalar_const_reference<T1>, E2, F> expression_type;
#ifdef BOOST_UBLAS_USE_ET
        typedef expression_type result_type;
#else
        typedef vector<typename F::result_type> result_type;
#endif
    };

    // (t * v) [i] = t * v [i]
    template<class T1, class E2>