vector_sparse.hpp

boost库提供标准的C++ API 配合dev c++使用,功能更加强大

        template<class AE>
        BOOST_UBLAS_INLINE
        sparse_vector (const vector_expression<AE> &ae, size_type non_zeros = 0):
            vector_expression<self_type> (),
            size_ (ae ().size ()), non_zeros_ (non_zeros), data_ () {
            reserve (non_zeros_);
            vector_assign (scalar_assign<reference, BOOST_UBLAS_TYPENAME AE::value_type> (), *this, ae);
        }

        // Accessors
        BOOST_UBLAS_INLINE
        size_type size () const {
            return size_;
        }
        BOOST_UBLAS_INLINE
        size_type non_zeros () const {
            return data_.size ();
        }
        BOOST_UBLAS_INLINE
        const_array_type &data () const {
            return data_;
        }
        BOOST_UBLAS_INLINE
        array_type &data () {
            return data_;
        }

        // Resizing
        BOOST_UBLAS_INLINE
        void resize (size_type size, size_type non_zeros = 0) {
            size_ = size;
            non_zeros_ = std::max (non_zeros, size_type (1));
            non_zeros_ = std::min (non_zeros_, size_);
            detail::reserve (data (), non_zeros_);
            data ().clear ();
        }

        // Reserving
        BOOST_UBLAS_INLINE
        void reserve (size_type non_zeros = 0) {
            non_zeros_ = std::max (non_zeros, size_type (1));
            non_zeros_ = std::min (non_zeros_, size_);
            detail::reserve (data (), non_zeros_);
        }

        // Proxy support
#ifdef BOOST_UBLAS_STRICT_VECTOR_SPARSE
        pointer find_element (size_type i) {
            iterator_type it (data ().find (i));
            if (it == data ().end () || (*it).first != i)
                return 0;
            return &(*it).second;
        }
#endif

        // Element access
        BOOST_UBLAS_INLINE
        const_reference operator () (size_type i) const {
            BOOST_UBLAS_CHECK (i < size_, bad_index ());
            const_iterator_type it (data ().find (i));
            if (it == data ().end () || (*it).first != i)
                return zero_;
            return (*it).second;
        }
        BOOST_UBLAS_INLINE
        reference operator () (size_type i) {
            BOOST_UBLAS_CHECK (i < size_, bad_index ());
#ifndef BOOST_UBLAS_STRICT_VECTOR_SPARSE
            return data () [i];
#else
            return reference (*this, i);
#endif
        }

        BOOST_UBLAS_INLINE
        const_reference operator [] (size_type i) const {
            return (*this) (i);
        }
        BOOST_UBLAS_INLINE
        reference operator [] (size_type i) {
            return (*this) (i);
        }

        // Assignment
        BOOST_UBLAS_INLINE
        sparse_vector &operator = (const sparse_vector &v) {
            // Too unusual semantic.
            // BOOST_UBLAS_CHECK (this != &v, external_logic ());
            if (this != &v) {
                // Precondition for container relaxed as requested during review.
                // BOOST_UBLAS_CHECK (size_ == v.size_, bad_size ());
                size_ = v.size_;
                non_zeros_ = v.non_zeros_;
                data () = v.data ();
            }
            return *this;
        }
        BOOST_UBLAS_INLINE
        sparse_vector &assign_temporary (sparse_vector &v) {
            swap (v);
            return *this;
        }
        template<class AE>
        BOOST_UBLAS_INLINE
        sparse_vector &operator = (const vector_expression<AE> &ae) {
#ifdef BOOST_UBLAS_MUTABLE_TEMPORARY
            return assign_temporary (self_type (ae, non_zeros_));
#else
            // return assign (self_type (ae, non_zeros_));
            self_type temporary (ae, non_zeros_);
            return assign_temporary (temporary);
#endif
        }
        template<class AE>
        BOOST_UBLAS_INLINE
        sparse_vector &reset (const vector_expression<AE> &ae) {
            self_type temporary (ae, non_zeros_);
            resize (temporary.size (), non_zeros_);
            return assign_temporary (temporary);
        }
        template<class AE>
        BOOST_UBLAS_INLINE
        sparse_vector &assign (const vector_expression<AE> &ae) {
            vector_assign (scalar_assign<reference, BOOST_UBLAS_TYPENAME AE::value_type> (), *this, ae);
            return *this;
        }
        template<class AE>
        BOOST_UBLAS_INLINE
        sparse_vector &operator += (const vector_expression<AE> &ae) {
#ifdef BOOST_UBLAS_MUTABLE_TEMPORARY
            return assign_temporary (self_type (*this + ae, non_zeros_));
#else
            // return assign (self_type (*this + ae, non_zeros_));
            self_type temporary (*this + ae, non_zeros_);
            return assign_temporary (temporary);
#endif
        }
        template<class AE>
        BOOST_UBLAS_INLINE
        sparse_vector &plus_assign (const vector_expression<AE> &ae) {
            vector_assign (scalar_plus_assign<reference, BOOST_UBLAS_TYPENAME AE::value_type> (), *this, ae);
            return *this;
        }
        template<class AE>
        BOOST_UBLAS_INLINE
        sparse_vector &operator -= (const vector_expression<AE> &ae) {
#ifdef BOOST_UBLAS_MUTABLE_TEMPORARY
            return assign_temporary (self_type (*this - ae, non_zeros_));
#else
            // return assign (self_type (*this - ae, non_zeros_));
            self_type temporary (*this - ae, non_zeros_);
            return assign_temporary (temporary);
#endif
        }
        template<class AE>
        BOOST_UBLAS_INLINE
        sparse_vector &minus_assign (const vector_expression<AE> &ae) {
            vector_assign (scalar_minus_assign<reference, BOOST_UBLAS_TYPENAME AE::value_type> (), *this, ae);
            return *this;
        }
        template<class AT>
        BOOST_UBLAS_INLINE
        sparse_vector &operator *= (const AT &at) {
            vector_assign_scalar (scalar_multiplies_assign<reference, AT> (), *this, at);
            return *this;
        }
        template<class AT>
        BOOST_UBLAS_INLINE
        sparse_vector &operator /= (const AT &at) {
            vector_assign_scalar (scalar_divides_assign<reference, AT> (), *this, at);
            return *this;
        }

        // Swapping
        BOOST_UBLAS_INLINE
        void swap (sparse_vector &v) {
            // Too unusual semantic.
            // BOOST_UBLAS_CHECK (this != &v, external_logic ());
            if (this != &v) {
                // Precondition for container relaxed as requested during review.
                // BOOST_UBLAS_CHECK (size_ == v.size_, bad_size ());
                // BOOST_UBLAS_CHECK (non_zeros_ == v.non_zeros_, bad_size ());
                std::swap (size_, v.size_);
                std::swap (non_zeros_, v.non_zeros_);
                data ().swap (v.data ());
            }
        }
#ifndef BOOST_UBLAS_NO_MEMBER_FRIENDS
        BOOST_UBLAS_INLINE
        friend void swap (sparse_vector &v1, sparse_vector &v2) {
            v1.swap (v2);
        }
#endif

        // Element insertion and erasure
        BOOST_UBLAS_INLINE
        void insert (size_type i, const_reference t) {
            BOOST_UBLAS_CHECK (data ().find (i) == data ().end (), bad_index ());
            data ().insert (data ().end (), std::pair<size_type, value_type> (i, t));
        }
        BOOST_UBLAS_INLINE
        void erase (size_type i) {
            // FIXME: shouldn't we use const_iterator_type here?
            iterator_type it = data ().find (i);
            if (it == data ().end ())
                return;
            data ().erase (it);
        }
        BOOST_UBLAS_INLINE
        void clear () {
            data ().clear ();
        }

        class const_iterator;
        class iterator;

        // Element lookup
        // This function seems to be big. So we do not let the compiler inline it.
        // BOOST_UBLAS_INLINE
        const_iterator find (size_type i) const {
            return const_iterator (*this, data ().lower_bound (i));
        }
        // This function seems to be big. So we do not let the compiler inline it.
        // BOOST_UBLAS_INLINE
        iterator find (size_type i) {
            return iterator (*this, data ().lower_bound (i));
        }

        // Iterators simply are pointers.

        class const_iterator:
            public container_const_reference<sparse_vector>,
            public bidirectional_iterator_base<sparse_bidirectional_iterator_tag,
                                               const_iterator, value_type> {
        public:
            typedef sparse_bidirectional_iterator_tag iterator_category;
#ifdef BOOST_MSVC_STD_ITERATOR
            typedef const_reference reference;
#else
            typedef typename sparse_vector::difference_type difference_type;
            typedef typename sparse_vector::value_type value_type;
            typedef typename sparse_vector::const_reference reference;
            typedef typename sparse_vector::const_pointer pointer;
#endif

            // Construction and destruction
            BOOST_UBLAS_INLINE
            const_iterator ():
                container_const_reference<self_type> (), it_ () {}
            BOOST_UBLAS_INLINE
            const_iterator (const self_type &v, const const_iterator_type &it):
                container_const_reference<self_type> (v), it_ (it) {}
#ifndef BOOST_UBLAS_QUALIFIED_TYPENAME
            BOOST_UBLAS_INLINE
            const_iterator (const iterator &it):
                container_const_reference<self_type> (it ()), it_ (it.it_) {}
#else
            BOOST_UBLAS_INLINE
            const_iterator (const typename self_type::iterator &it):
                container_const_reference<self_type> (it ()), it_ (it.it_) {}
#endif
            // Arithmetic
            BOOST_UBLAS_INLINE
            const_iterator &operator ++ () {
                ++ it_;
                return *this;
            }
            BOOST_UBLAS_INLINE
            const_iterator &operator -- () {
                -- it_;
                return *this;
            }

            // Dereference
            BOOST_UBLAS_INLINE
            reference operator * () const {
                BOOST_UBLAS_CHECK (index () < (*this) ().size (), bad_index ());
                return (*it_).second;
            }

            // Index
            BOOST_UBLAS_INLINE
            size_type index () const {
                return (*it_).first;
            }

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

            // Comparison
            BOOST_UBLAS_INLINE
            bool operator == (const const_iterator &it) const {
                // FIXME: won't work with vector of vectors.
                // BOOST_UBLAS_CHECK (&(*this) () == &it (), external_logic ());
                return &(*this) () == &it () && it_ == it.it_;
            }

        private:
            const_iterator_type it_;
        };

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

        class iterator:
            public container_reference<sparse_vector>,
            public bidirectional_iterator_base<sparse_bidirectional_iterator_tag,
                                               iterator, value_type> {
        public:
            typedef sparse_bidirectional_iterator_tag iterator_category;
#ifndef BOOST_MSVC_STD_ITERATOR
            typedef typename sparse_vector::difference_type difference_type;
            typedef typename sparse_vector::value_type value_type;
            typedef typename sparse_vector::reference reference;
            typedef typename sparse_vector::pointer pointer;
#endif

            // Construction and destruction
            BOOST_UBLAS_INLINE
            iterator ():
                container_reference<self_type> (), it_ () {}
            BOOST_UBLAS_INLINE
            iterator (self_type &v, const iterator_type &it):
                container_reference<self_type> (v), it_ (it) {}

            // Arithmetic
            BOOST_UBLAS_INLINE
            iterator &operator ++ () {
                ++ it_;
                return *this;
            }