c++boost.gifVector Proxies

Vector Range

Description

The templated class vector_range<V> allows addressing a range of a vector.

Example

int main () {
    using namespace boost::numeric::ublas;
    vector<double> v (3);
    vector_range<vector<double> > vr (v, range (0, 3));
    for (int i = 0; i < vr.size (); ++ i)
        vr (i) = i;
    std::cout << vr << std::endl;
}

Definition

Defined in the header vector_proxy.hpp.

Template parameters

Parameter Description Default
V The type of vector referenced.  

Model of

Vector Expression.

Type requirements

None, except for those imposed by the requirements of Vector Expression.

Public base classes

vector_expression<vector_range<V> >

Members

Member Description
vector_range (vector_type &data, const range &r) Constructs a sub vector.
size_type start () const Returns the start of the sub vector.
size_type size () const Returns the size of the sub vector.
const_reference operator () (size_type i) const Returns the value of the i-th element.
reference operator () (size_type i) Returns a reference of the i-th element.
const_reference operator [] (size_type i) const Returns the value of the i-th element.
reference operator [] (size_type i) Returns a reference of the i-th element.
vector_range &operator = (const vector_range &vr) The assignment operator.
vector_range &assign_temporary (vector_range &vr) Assigns a temporary. May change the vector range vr.
template<class AE>
vector_range &operator = (const vector_expression<AE> &ae)
The extended assignment operator.
template<class AE>
vector_range &assign (const vector_expression<AE> &ae)
Assigns a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
template<class AE>
vector_range &operator += (const vector_expression<AE> &ae)
A computed assignment operator. Adds the vector expression to the sub vector.
template<class AE>
vector_range &plus_assign (const vector_expression<AE> &ae)
Adds a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
template<class AE>
vector_range &operator -= (const vector_expression<AE> &ae)
A computed assignment operator. Subtracts the vector expression from the sub vector.
template<class AE>
vector_range &minus_assign (const vector_expression<AE> &ae)
Subtracts a vector expression from the sub vector. Left and right hand side of the assignment should be independent.
template<class AT>
vector_range &operator *= (const AT &at)
A computed assignment operator. Multiplies the sub vector with a scalar.
template<class AT>
vector_range &operator /= (const AT &at)
A computed assignment operator. Divides the sub vector through a scalar.
void swap (vector_range &vr) Swaps the contents of the sub vectors.
const_iterator begin () const Returns a const_iterator pointing to the beginning of the vector_range.
const_iterator end () const Returns a const_iterator pointing to the end of the vector_range.
iterator begin () Returns a iterator pointing to the beginning of the vector_range.
iterator end () Returns a iterator pointing to the end of the vector_range.
const_reverse_iterator rbegin () const Returns a const_reverse_iterator pointing to the beginning of the reversed vector_range.
const_reverse_iterator rend () const Returns a const_reverse_iterator pointing to the end of the reversed vector_range.
reverse_iterator rbegin () Returns a reverse_iterator pointing to the beginning of the reversed vector_range.
reverse_iterator rend () Returns a reverse_iterator pointing to the end of the reversed vector_range.

Interface

    // Vector based range class
    template<class V>
    class vector_range:
        public vector_expression<vector_range<V> > {
    public:      
        typedef const V const_vector_type;
        typedef V vector_type;
        typedef typename V::size_type size_type;
        typedef typename V::difference_type difference_type;
        typedef typename V::value_type value_type;
        typedef typename V::const_reference const_reference;
        typedef typename V::reference reference;
        typedef typename V::const_pointer const_pointer;
        typedef typename V::pointer pointer;
        typedef const vector_const_reference<const vector_range<vector_type> > const_closure_type;
        typedef vector_reference<vector_range<vector_type> > closure_type;
        typedef typename V::const_iterator const_iterator_type;
        typedef typename V::iterator iterator_type;
        typedef typename storage_restrict_traits<typename V::storage_category,
                                                 dense_proxy_tag>::storage_category storage_category;

        // Construction and destruction
        vector_range (); 
        vector_range (vector_type &data, const range &r); 

        // Accessors
        size_type start () const; 
        size_type size () const; 
        const_vector_type &data () const;
        vector_type &data ();


        // Element access
        const_reference operator () (size_type i) const;
        reference operator () (size_type i);

        const_reference operator [] (size_type i) const;
        reference operator [] (size_type i);

        vector_range<vector_type> project (const range &r) const;

        // Assignment
        vector_range &operator = (const vector_range &vr);
        vector_range &assign_temporary (vector_range &vr);
        template<class AE>
        vector_range &operator = (const vector_expression<AE> &ae);
        template<class AE>
        vector_range &assign (const vector_expression<AE> &ae);
        template<class AE>
        vector_range &operator += (const vector_expression<AE> &ae);
        template<class AE>
        vector_range &plus_assign (const vector_expression<AE> &ae);
        template<class AE>
        vector_range &operator -= (const vector_expression<AE> &ae);
        template<class AE>
        vector_range &minus_assign (const vector_expression<AE> &ae);
        template<class AT>
        vector_range &operator *= (const AT &at);
        template<class AT>
        vector_range &operator /= (const AT &at);

        // Swapping
        void swap (vector_range &vr);
        friend void swap (vector_range &vr1, vector_range &vr2);

        class const_iterator;
        class iterator;

        // Element lookup
        const_iterator find_first (size_type i) const;
        iterator find_first (size_type i);
        const_iterator find_last (size_type i) const;
        iterator find_last (size_type i);

        // Iterators simply are pointers.

        class const_iterator:
            public container_const_reference<vector_range>,
            public random_access_iterator_base<const_iterator, value_type> {
        public:
            typedef typename V::const_iterator::iterator_category iterator_category;
            typedef typename V::const_iterator::difference_type difference_type;
            typedef typename V::const_iterator::value_type value_type;
            typedef typename V::const_iterator::reference reference;
            typedef typename V::const_iterator::pointer pointer;

            // Construction and destruction
            const_iterator ();
            const_iterator (const vector_range &vr, const const_iterator_type &it);
            const_iterator (const iterator &it);

            // Arithmetic
            const_iterator &operator ++ ();
            const_iterator &operator -- ();
            const_iterator &operator += (difference_type n);
            const_iterator &operator -= (difference_type n);
            difference_type operator - (const const_iterator &it) const;

            // Dereference
            reference operator * () const;

            // Index
            size_type index () const;

            // Assignment 
            const_iterator &operator = (const const_iterator &it);

            // Comparison
            bool operator == (const const_iterator &it) const;
            bool operator <(const const_iterator &it) const;
        };

        const_iterator begin () const;
        const_iterator end () const;

        class iterator:
            public container_reference<vector_range>,
            public random_access_iterator_base<iterator, value_type> {
        public:
            typedef typename V::iterator::iterator_category iterator_category;
            typedef typename V::iterator::difference_type difference_type;
            typedef typename V::iterator::value_type value_type;
            typedef typename V::iterator::reference reference;
            typedef typename V::iterator::pointer pointer;

            // Construction and destruction
            iterator ();
            iterator (vector_range &vr, const iterator_type &it);

            // Arithmetic
            iterator &operator ++ ();
            iterator &operator -- ();
            iterator &operator += (difference_type n);
            iterator &operator -= (difference_type n);
            difference_type operator - (const iterator &it) const;

            // Dereference
            reference operator * () const;

            // Index
            size_type index () const;

            // Assignment 
            iterator &operator = (const iterator &it);

            // Comparison
            bool operator == (const iterator &it) const;
            bool operator <(const iterator &it) const;
        };

        iterator begin ();
        iterator end ();

        // Reverse iterator

        typedef reverse_iterator_base<const_iterator> const_reverse_iterator;

        const_reverse_iterator rbegin () const;
        const_reverse_iterator rend () const;

        typedef reverse_iterator_base<iterator> reverse_iterator;

        reverse_iterator rbegin ();
        reverse_iterator rend ();
    };

Projections

Prototypes

    template<class V>
    vector_range<V> project (V &data, const range &r);
    template<class V>
    const vector_range<const V> project (const V &data, const range &r);
    template<class V>
    vector_range<V> project (const vector_range<V> &data, const range &r);

Description

The free project functions support the construction of vector ranges.

Definition

Defined in the header vector_proxy.hpp.

Type requirements

  • V is a model of Vector Expression.
  • Preconditions

  • r.start () + r.size () <= data.size ()
  • Complexity

    Linear depending from the size of the range.

    Examples

    int main () {
        using namespace boost::numeric::ublas;
        vector<double> v (3);
        for (int i = 0; i < 3; ++ i)
            project (v, range (0, 3)) (i) = i;
        std::cout << project (v, range (0, 3)) << std::endl;
    }

    Vector Slice

    Description

    The templated class vector_slice<V> allows addressing a slice of a vector.

    Example

    int main () {
        using namespace boost::numeric::ublas;
        vector<double> v (3);
        vector_slice<vector<double> > vs (v, slice (0, 1, 3));
        for (int i = 0; i < vs.size (); ++ i) 
            vs (i) = i;
        std::cout << vs << std::endl;
    }

    Definition

    Defined in the header vector_proxy.hpp.

    Template parameters

    Parameter Description Default
    V The type of vector referenced.  

    Model of

    Vector Expression.

    Type requirements

    None, except for those imposed by the requirements of Vector Expression.

    Public base classes

    vector_expression<vector_slice<V> >

    Members

    Member Description
    vector_slice (vector_type &data, const slice &s) Constructs a sub vector.
    size_type size () const Returns the size of the sub vector.
    const_reference operator () (size_type i) const Returns the value of the i-th element.
    reference operator () (size_type i) Returns a reference of the i-th element.
    const_reference operator [] (size_type i) const Returns the value of the i-th element.
    reference operator [] (size_type i) Returns a reference of the i-th element.
    vector_slice &operator = (const vector_slice &vs) The assignment operator.
    vector_slice &assign_temporary (vector_slice &vs) Assigns a temporary. May change the vector slice vs.
    template<class AE>
    vector_slice &operator = (const vector_expression<AE> &ae)
    The extended assignment operator.
    template<class AE>
    vector_slice &assign (const vector_expression<AE> &ae)
    Assigns a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
    template<class AE>
    vector_slice &operator += (const vector_expression<AE> &ae)
    A computed assignment operator. Adds the vector expression to the sub vector.
    template<class AE>
    vector_slice &plus_assign (const vector_expression<AE> &ae)
    Adds a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
    template<class AE>
    vector_slice &operator -= (const vector_expression<AE> &ae)
    A computed assignment operator. Subtracts the vector expression from the sub vector.
    template<class AE>
    vector_slice &minus_assign (const vector_expression<AE> &ae)
    Subtracts a vector expression from the sub vector. Left and right hand side of the assignment should be independent.
    template<class AT>
    vector_slice &operator *= (const AT &at)
    A computed assignment operator. Multiplies the sub vector with a scalar.
    template<class AT>
    vector_slice &operator /= (const AT &at)
    A computed assignment operator. Divides the sub vector through a scalar.
    void swap (vector_slice &vs) Swaps the contents of the sub vectors.
    const_iterator begin () const Returns a const_iterator pointing to the beginning of the vector_slice.
    const_iterator end () const Returns a const_iterator pointing to the end of the vector_slice.
    iterator begin () Returns a iterator pointing to the beginning of the vector_slice.
    iterator end () Returns a iterator pointing to the end of the vector_slice.
    const_reverse_iterator rbegin () const Returns a const_reverse_iterator pointing to the beginning of the reversed vector_slice.
    const_reverse_iterator rend () const Returns a const_reverse_iterator pointing to the end of the reversed vector_slice.
    reverse_iterator rbegin () Returns a reverse_iterator pointing to the beginning of the reversed vector_slice.
    reverse_iterator rend () Returns a reverse_iterator pointing to the end of the reversed vector_slice.

    Interface

        // Vector based slice class
        template<class V>
        class vector_slice:
            public vector_expression<vector_slice<V> > {
        public:      
            typedef const V const_vector_type;
            typedef V vector_type;
            typedef typename V::size_type size_type;
            typedef typename V::difference_type difference_type;
            typedef typename V::value_type value_type;
            typedef typename V::const_reference const_reference;
            typedef typename V::reference reference;
            typedef typename V::const_pointer const_pointer;
            typedef typename V::pointer pointer;
            typedef const vector_const_reference<const vector_slice<vector_type> > const_closure_type;
            typedef vector_reference<vector_slice<vector_type> > closure_type;
            typedef slice::const_iterator const_iterator_type;
            typedef slice::const_iterator iterator_type;
            typedef typename storage_restrict_traits<typename V::storage_category,
                                                     dense_proxy_tag>::storage_category storage_category;
    
            // Construction and destruction
            vector_slice ();
            vector_slice (vector_type &data, const slice &s);
    
            // Accessors
            size_type start () const;
            size_type stride () const;
            size_type size () const;
            const_vector_type &data () const;
            vector_type &data ();
    
    
            // Element access
            const_reference operator () (size_type i) const;
            reference operator () (size_type i);
    
            const_reference operator [] (size_type i) const;
            reference operator [] (size_type i);
    
            vector_slice<vector_type> project (const range &r) const;
            vector_slice<vector_type> project (const slice &s) const;
    
            // Assignment
            vector_slice &operator = (const vector_slice &vs);
            vector_slice &assign_temporary (vector_slice &vs);
            template<class AE>
            vector_slice &operator = (const vector_expression<AE> &ae);
            template<class AE>
            vector_slice &assign (const vector_expression<AE> &ae);
            template<class AE>
            vector_slice &operator += (const vector_expression<AE> &ae);
            template<class AE>
            vector_slice &plus_assign (const vector_expression<AE> &ae);
            template<class AE>
            vector_slice &operator -= (const vector_expression<AE> &ae);
            template<class AE>
            vector_slice &minus_assign (const vector_expression<AE> &ae);
            template<class AT>
            vector_slice &operator *= (const AT &at);
            template<class AT>
            vector_slice &operator /= (const AT &at);
    
            // Swapping
            void swap (vector_slice &vs);
            friend void swap (vector_slice &vs1, vector_slice &vs2);
    
            class const_iterator;
            class iterator;
    
            // Element lookup
            const_iterator find_first (size_type i) const;
            iterator find_first (size_type i);
            const_iterator find_last (size_type i) const;
            iterator find_last (size_type i);
    
            // Iterators simply are indices.
    
            class const_iterator:
                public container_const_reference<vector_slice>,
                public random_access_iterator_base<const_iterator, value_type> {
            public:
                typedef typename V::const_iterator::iterator_category iterator_category;
                typedef typename V::const_iterator::difference_type difference_type;
                typedef typename V::const_iterator::value_type value_type;
                typedef typename V::const_iterator::reference reference;
                typedef typename V::const_iterator::pointer pointer;
    
                // Construction and destruction
                const_iterator ();
                const_iterator (const vector_slice &vs, const const_iterator_type &it);
                const_iterator (const iterator &it);
    
                // Arithmetic
                const_iterator &operator ++ ();
                const_iterator &operator -- ();
                const_iterator &operator += (difference_type n);
                const_iterator &operator -= (difference_type n);
                difference_type operator - (const const_iterator &it) const;
    
                // Dereference
                reference operator * () const;
    
                // Index
                size_type index () const;
    
                // Assignment 
                const_iterator &operator = (const const_iterator &it);
    
                // Comparison
                bool operator == (const const_iterator &it) const;
                bool operator <(const const_iterator &it) const;
            };
    
            const_iterator begin () const;
            const_iterator end () const;
    
            class iterator:
                public container_reference<vector_slice>,
                public random_access_iterator_base<iterator, value_type> {
            public:
                typedef typename V::iterator::iterator_category iterator_category;
                typedef typename V::iterator::difference_type difference_type;
                typedef typename V::iterator::value_type value_type;
                typedef typename V::iterator::reference reference;
                typedef typename V::iterator::pointer pointer;
    
                // Construction and destruction
                iterator ();
                iterator (vector_slice &vs, const iterator_type &it);
    
                // Arithmetic
                iterator &operator ++ ();
                iterator &operator -- ();
                iterator &operator += (difference_type n);
                iterator &operator -= (difference_type n);
                difference_type operator - (const iterator &it) const;
    
                // Dereference
                reference operator * () const;
    
                // Index
                size_type index () const;
    
                // Assignment 
                iterator &operator = (const iterator &it);
    
                // Comparison
                bool operator == (const iterator &it) const;
                bool operator <(const iterator &it) const;
            };
    
            iterator begin ();
            iterator end ();
    
            // Reverse iterator
    
            typedef reverse_iterator_base<const_iterator> const_reverse_iterator;
    
            const_reverse_iterator rbegin () const;
            const_reverse_iterator rend () const;
    
            typedef reverse_iterator_base<iterator> reverse_iterator;
    
            reverse_iterator rbegin ();
            reverse_iterator rend ();
        };

    Projections

    Prototypes

        template<class V>
        vector_slice<V> project (const vector_slice<V> &data, const range &r);
        template<class V>
        vector_slice<V> project (V &data, const slice &s);
        template<class V>
        const vector_slice<const V> project (const V &data, const slice &s);
        template<class V>
        vector_slice<V> project (const vector_slice<V> &data, const slice &s);

    Description

    The free project functions support the construction of vector slices.

    Definition

    Defined in the header vector_proxy.hpp.

    Type requirements

  • V is a model of Vector Expression.
  • Preconditions

    Complexity

    Linear depending from the size of the slice.

    Examples

    int main () {
        using namespace boost::numeric::ublas;
        vector<double> v (3);
        for (int i = 0; i < 3; ++ i)
            project (v, slice (0, 1, 3)) (i) = i;
        std::cout << project (v, slice (0, 1, 3)) << std::endl;
    }

    Copyright () 2000-2002 Joerg Walter, Mathias Koch
    Permission to copy, use, modify, sell and distribute this document is granted provided this copyright notice appears in all copies. This document is provided ``as is'' without express or implied warranty, and with no claim as to its suitability for any purpose.

    Last revised: 8/3/2002