Reference documentation for deal.II version Git 053e5b2 2017-07-21 22:33:36 -0600
Public Types | Public Member Functions | Protected Attributes | Friends | List of all members
BlockVectorBase< VectorType > Class Template Reference

#include <deal.II/lac/block_vector_base.h>

Inheritance diagram for BlockVectorBase< VectorType >:
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Public Types

typedef VectorType BlockType
 
typedef BlockType::real_type real_type
 

Public Member Functions

 BlockVectorBase ()=default
 
 BlockVectorBase (const BlockVectorBase &)=default
 
 BlockVectorBase (BlockVectorBase &&)=default
 
void collect_sizes ()
 
void compress (::VectorOperation::values operation)
 
BlockTypeblock (const unsigned int i)
 
const BlockTypeblock (const unsigned int i) const
 
const BlockIndicesget_block_indices () const
 
unsigned int n_blocks () const
 
std::size_t size () const
 
IndexSet locally_owned_elements () const
 
iterator begin ()
 
const_iterator begin () const
 
iterator end ()
 
const_iterator end () const
 
value_type operator() (const size_type i) const
 
reference operator() (const size_type i)
 
value_type operator[] (const size_type i) const
 
reference operator[] (const size_type i)
 
template<typename OtherNumber >
void extract_subvector_to (const std::vector< size_type > &indices, std::vector< OtherNumber > &values) const
 
template<typename ForwardIterator , typename OutputIterator >
void extract_subvector_to (ForwardIterator indices_begin, const ForwardIterator indices_end, OutputIterator values_begin) const
 
BlockVectorBaseoperator= (const value_type s)
 
BlockVectorBaseoperator= (const BlockVectorBase &V)
 
BlockVectorBaseoperator= (BlockVectorBase &&)=default
 
template<class VectorType2 >
BlockVectorBaseoperator= (const BlockVectorBase< VectorType2 > &V)
 
BlockVectorBaseoperator= (const VectorType &v)
 
template<class VectorType2 >
bool operator== (const BlockVectorBase< VectorType2 > &v) const
 
value_type operator* (const BlockVectorBase &V) const
 
real_type norm_sqr () const
 
value_type mean_value () const
 
real_type l1_norm () const
 
real_type l2_norm () const
 
real_type linfty_norm () const
 
value_type add_and_dot (const value_type a, const BlockVectorBase &V, const BlockVectorBase &W)
 
bool in_local_range (const size_type global_index) const
 
bool all_zero () const
 
bool is_non_negative () const
 
BlockVectorBaseoperator+= (const BlockVectorBase &V)
 
BlockVectorBaseoperator-= (const BlockVectorBase &V)
 
template<typename Number >
void add (const std::vector< size_type > &indices, const std::vector< Number > &values)
 
template<typename Number >
void add (const std::vector< size_type > &indices, const Vector< Number > &values)
 
template<typename Number >
void add (const size_type n_elements, const size_type *indices, const Number *values)
 
void add (const value_type s)
 
void add (const value_type a, const BlockVectorBase &V)
 
void add (const value_type a, const BlockVectorBase &V, const value_type b, const BlockVectorBase &W)
 
void sadd (const value_type s, const BlockVectorBase &V)
 
void sadd (const value_type s, const value_type a, const BlockVectorBase &V)
 
void sadd (const value_type s, const value_type a, const BlockVectorBase &V, const value_type b, const BlockVectorBase &W)
 
void sadd (const value_type s, const value_type a, const BlockVectorBase &V, const value_type b, const BlockVectorBase &W, const value_type c, const BlockVectorBase &X)
 
BlockVectorBaseoperator*= (const value_type factor)
 
BlockVectorBaseoperator/= (const value_type factor)
 
template<class BlockVector2 >
void scale (const BlockVector2 &v)
 
template<class BlockVector2 >
void equ (const value_type a, const BlockVector2 &V)
 
void equ (const value_type a, const BlockVectorBase &V, const value_type b, const BlockVectorBase &W)
 
void update_ghost_values () const
 
std::size_t memory_consumption () const
 
- Public Member Functions inherited from Subscriptor
 Subscriptor ()
 
 Subscriptor (const Subscriptor &)
 
 Subscriptor (Subscriptor &&)
 
virtual ~Subscriptor ()
 
Subscriptoroperator= (const Subscriptor &)
 
Subscriptoroperator= (Subscriptor &&)
 
void subscribe (const char *identifier=nullptr) const
 
void unsubscribe (const char *identifier=nullptr) const
 
unsigned int n_subscriptions () const
 
void list_subscribers () const
 
template<class Archive >
void serialize (Archive &ar, const unsigned int version)
 

Protected Attributes

std::vector< VectorType > components
 
BlockIndices block_indices
 

Friends

template<typename N , bool C>
class ::internal::BlockVectorIterators::Iterator
 
template<typename >
class BlockVectorBase
 

Additional Inherited Members

- Static Public Member Functions inherited from Subscriptor
static::ExceptionBase & ExcInUse (int arg1, char *arg2, std::string &arg3)
 
static::ExceptionBase & ExcNoSubscriber (char *arg1, char *arg2)
 

Detailed Description

template<class VectorType>
class BlockVectorBase< VectorType >

A vector composed of several blocks each representing a vector of its own.

The BlockVector is a collection of vectors of a given type (e.g., deal.II Vector objects, PETScWrappers::MPI::Vector objects, etc.). Each of the vectors inside can have a different size.

The functionality of BlockVector includes everything a Vector can do, plus the access to a single Vector inside the BlockVector by block(i). It also has a complete random access iterator, just as the other Vector classes or the standard C++ library template std::vector. Therefore, all algorithms working on iterators also work with objects of this class.

While this base class implements most of the functionality by dispatching calls to its member functions to the respective functions on each of the individual blocks, this class does not actually allocate some memory or change the size of vectors. For this, the constructors, assignment operators and reinit() functions of derived classes are responsible. This class only handles the common part that is independent of the actual vector type the block vector is built on.

Accessing individual blocks, and resizing vectors

Apart from using this object as a whole, you can use each block separately as a vector, using the block() function. There is a single caveat: if you have changed the size of one or several blocks, you must call the function collect_sizes() of the block vector to update its internal structures.

Attention
Warning: If you change the sizes of single blocks without calling collect_sizes(), results may be unpredictable. The debug version does not check consistency here for performance reasons!
See also
Block (linear algebra)
Author
Wolfgang Bangerth, Guido Kanschat, 1999, 2000, 2001, 2002, 2004

Definition at line 39 of file block_vector_base.h.

Member Typedef Documentation

template<class VectorType>
typedef VectorType BlockVectorBase< VectorType >::BlockType

Typedef the type of the underlying vector.

Definition at line 519 of file block_vector_base.h.

template<class VectorType>
typedef BlockType::real_type BlockVectorBase< VectorType >::real_type

Declare a type that has holds real-valued numbers with the same precision as the template argument to this class. If the template argument of this class is a real data type, then real_type equals the template argument. If the template argument is a std::complex type then real_type equals the type underlying the complex numbers.

This typedef is used to represent the return type of norms.

Definition at line 549 of file block_vector_base.h.

Constructor & Destructor Documentation

template<class VectorType>
BlockVectorBase< VectorType >::BlockVectorBase ( )
default

Default constructor.

template<class VectorType>
BlockVectorBase< VectorType >::BlockVectorBase ( const BlockVectorBase< VectorType > &  )
default

Copy constructor.

template<class VectorType>
BlockVectorBase< VectorType >::BlockVectorBase ( BlockVectorBase< VectorType > &&  )
default

Move constructor. Each block of the argument vector is moved into the current object if the underlying VectorType is move-constructible, otherwise they are copied.

Member Function Documentation

template<class VectorType>
void BlockVectorBase< VectorType >::collect_sizes ( )

Update internal structures after resizing vectors. Whenever you reinited a block of a block vector, the internal data structures are corrupted. Therefore, you should call this function after all blocks got their new size.

template<class VectorType>
void BlockVectorBase< VectorType >::compress ( ::VectorOperation::values  operation)

Call the compress() function on all the subblocks of the matrix.

This functionality only needs to be called if using MPI based vectors and exists in other objects for compatibility.

See Compressing distributed objects for more information.

template<class VectorType>
BlockType& BlockVectorBase< VectorType >::block ( const unsigned int  i)

Access to a single block.

template<class VectorType>
const BlockType& BlockVectorBase< VectorType >::block ( const unsigned int  i) const

Read-only access to a single block.

template<class VectorType>
const BlockIndices& BlockVectorBase< VectorType >::get_block_indices ( ) const

Return a reference on the object that describes the mapping between block and global indices. The use of this function is highly deprecated and it should vanish in one of the next versions

template<class VectorType>
unsigned int BlockVectorBase< VectorType >::n_blocks ( ) const

Number of blocks.

template<class VectorType>
std::size_t BlockVectorBase< VectorType >::size ( ) const

Return dimension of the vector. This is the sum of the dimensions of all components.

template<class VectorType>
IndexSet BlockVectorBase< VectorType >::locally_owned_elements ( ) const

Return an index set that describes which elements of this vector are owned by the current processor. Note that this index set does not include elements this vector may store locally as ghost elements but that are in fact owned by another processor. As a consequence, the index sets returned on different processors if this is a distributed vector will form disjoint sets that add up to the complete index set. Obviously, if a vector is created on only one processor, then the result would satisfy

vec.locally_owned_elements() == complete_index_set (vec.size())

For block vectors, this function returns the union of the locally owned elements of the individual blocks, shifted by their respective index offsets.

template<class VectorType>
iterator BlockVectorBase< VectorType >::begin ( )

Return an iterator pointing to the first element.

template<class VectorType>
const_iterator BlockVectorBase< VectorType >::begin ( ) const

Return an iterator pointing to the first element of a constant block vector.

template<class VectorType>
iterator BlockVectorBase< VectorType >::end ( )

Return an iterator pointing to the element past the end.

template<class VectorType>
const_iterator BlockVectorBase< VectorType >::end ( ) const

Return an iterator pointing to the element past the end of a constant block vector.

template<class VectorType>
value_type BlockVectorBase< VectorType >::operator() ( const size_type  i) const

Access components, returns U(i).

template<class VectorType>
reference BlockVectorBase< VectorType >::operator() ( const size_type  i)

Access components, returns U(i) as a writeable reference.

template<class VectorType>
value_type BlockVectorBase< VectorType >::operator[] ( const size_type  i) const

Access components, returns U(i).

Exactly the same as operator().

template<class VectorType>
reference BlockVectorBase< VectorType >::operator[] ( const size_type  i)

Access components, returns U(i) as a writeable reference.

Exactly the same as operator().

template<class VectorType>
template<typename OtherNumber >
void BlockVectorBase< VectorType >::extract_subvector_to ( const std::vector< size_type > &  indices,
std::vector< OtherNumber > &  values 
) const

A collective get operation: instead of getting individual elements of a vector, this function allows to get a whole set of elements at once. The indices of the elements to be read are stated in the first argument, the corresponding values are returned in the second.

template<class VectorType>
template<typename ForwardIterator , typename OutputIterator >
void BlockVectorBase< VectorType >::extract_subvector_to ( ForwardIterator  indices_begin,
const ForwardIterator  indices_end,
OutputIterator  values_begin 
) const

Just as the above, but with pointers. Useful in minimizing copying of data around.

template<class VectorType>
BlockVectorBase& BlockVectorBase< VectorType >::operator= ( const value_type  s)

Copy operator: fill all components of the vector with the given scalar value.

template<class VectorType>
BlockVectorBase& BlockVectorBase< VectorType >::operator= ( const BlockVectorBase< VectorType > &  V)

Copy operator for arguments of the same type.

template<class VectorType>
BlockVectorBase& BlockVectorBase< VectorType >::operator= ( BlockVectorBase< VectorType > &&  )
default

Move assignment operator. Move each block of the given argument vector into the current object if VectorType is move-constructible, otherwise copy them.

template<class VectorType>
template<class VectorType2 >
BlockVectorBase& BlockVectorBase< VectorType >::operator= ( const BlockVectorBase< VectorType2 > &  V)

Copy operator for template arguments of different types.

template<class VectorType>
BlockVectorBase& BlockVectorBase< VectorType >::operator= ( const VectorType &  v)

Copy operator from non-block vectors to block vectors.

template<class VectorType>
template<class VectorType2 >
bool BlockVectorBase< VectorType >::operator== ( const BlockVectorBase< VectorType2 > &  v) const

Check for equality of two block vector types. This operation is only allowed if the two vectors already have the same block structure.

template<class VectorType>
value_type BlockVectorBase< VectorType >::operator* ( const BlockVectorBase< VectorType > &  V) const

\(U = U * V\): scalar product.

template<class VectorType>
real_type BlockVectorBase< VectorType >::norm_sqr ( ) const

Return square of the \(l_2\)-norm.

template<class VectorType>
value_type BlockVectorBase< VectorType >::mean_value ( ) const

Return the mean value of the elements of this vector.

template<class VectorType>
real_type BlockVectorBase< VectorType >::l1_norm ( ) const

Return the \(l_1\)-norm of the vector, i.e. the sum of the absolute values.

template<class VectorType>
real_type BlockVectorBase< VectorType >::l2_norm ( ) const

Return the \(l_2\)-norm of the vector, i.e. the square root of the sum of the squares of the elements.

template<class VectorType>
real_type BlockVectorBase< VectorType >::linfty_norm ( ) const

Return the maximum absolute value of the elements of this vector, which is the \(l_\infty\)-norm of a vector.

template<class VectorType>
value_type BlockVectorBase< VectorType >::add_and_dot ( const value_type  a,
const BlockVectorBase< VectorType > &  V,
const BlockVectorBase< VectorType > &  W 
)

Performs a combined operation of a vector addition and a subsequent inner product, returning the value of the inner product. In other words, the result of this function is the same as if the user called

this->add(a, V);
return_value = *this * W;

The reason this function exists is that this operation involves less memory transfer than calling the two functions separately on deal.II's vector classes (Vector<Number> and LinearAlgebra::distributed::Vector<double>). This method only needs to load three vectors, this, V, W, whereas calling separate methods means to load the calling vector this twice. Since most vector operations are memory transfer limited, this reduces the time by 25% (or 50% if W equals this).

template<class VectorType>
bool BlockVectorBase< VectorType >::in_local_range ( const size_type  global_index) const

Return true if the given global index is in the local range of this processor. Asks the corresponding block.

template<class VectorType>
bool BlockVectorBase< VectorType >::all_zero ( ) const

Return whether the vector contains only elements with value zero. This function is mainly for internal consistency check and should seldom be used when not in debug mode since it uses quite some time.

template<class VectorType>
bool BlockVectorBase< VectorType >::is_non_negative ( ) const

Return true if the vector has no negative entries, i.e. all entries are zero or positive. This function is used, for example, to check whether refinement indicators are really all positive (or zero).

template<class VectorType>
BlockVectorBase& BlockVectorBase< VectorType >::operator+= ( const BlockVectorBase< VectorType > &  V)

Addition operator. Fast equivalent to U.add(1, V).

template<class VectorType>
BlockVectorBase& BlockVectorBase< VectorType >::operator-= ( const BlockVectorBase< VectorType > &  V)

Subtraction operator. Fast equivalent to U.add(-1, V).

template<class VectorType>
template<typename Number >
void BlockVectorBase< VectorType >::add ( const std::vector< size_type > &  indices,
const std::vector< Number > &  values 
)

A collective add operation: This function adds a whole set of values stored in values to the vector components specified by indices.

template<class VectorType>
template<typename Number >
void BlockVectorBase< VectorType >::add ( const std::vector< size_type > &  indices,
const Vector< Number > &  values 
)

This is a second collective add operation. As a difference, this function takes a deal.II vector of values.

template<class VectorType>
template<typename Number >
void BlockVectorBase< VectorType >::add ( const size_type  n_elements,
const size_type *  indices,
const Number *  values 
)

Take an address where n_elements are stored contiguously and add them into the vector. Handles all cases which are not covered by the other two add() functions above.

template<class VectorType>
void BlockVectorBase< VectorType >::add ( const value_type  s)

\(U(0-DIM)+=s\). Addition of s to all components. Note that s is a scalar and not a vector.

template<class VectorType>
void BlockVectorBase< VectorType >::add ( const value_type  a,
const BlockVectorBase< VectorType > &  V 
)

U+=a*V. Simple addition of a scaled vector.

template<class VectorType>
void BlockVectorBase< VectorType >::add ( const value_type  a,
const BlockVectorBase< VectorType > &  V,
const value_type  b,
const BlockVectorBase< VectorType > &  W 
)

U+=a*V+b*W. Multiple addition of scaled vectors.

template<class VectorType>
void BlockVectorBase< VectorType >::sadd ( const value_type  s,
const BlockVectorBase< VectorType > &  V 
)

U=s*U+V. Scaling and simple vector addition.

template<class VectorType>
void BlockVectorBase< VectorType >::sadd ( const value_type  s,
const value_type  a,
const BlockVectorBase< VectorType > &  V 
)

U=s*U+a*V. Scaling and simple addition.

template<class VectorType>
void BlockVectorBase< VectorType >::sadd ( const value_type  s,
const value_type  a,
const BlockVectorBase< VectorType > &  V,
const value_type  b,
const BlockVectorBase< VectorType > &  W 
)

U=s*U+a*V+b*W. Scaling and multiple addition.

template<class VectorType>
void BlockVectorBase< VectorType >::sadd ( const value_type  s,
const value_type  a,
const BlockVectorBase< VectorType > &  V,
const value_type  b,
const BlockVectorBase< VectorType > &  W,
const value_type  c,
const BlockVectorBase< VectorType > &  X 
)

U=s*U+a*V+b*W+c*X. Scaling and multiple addition.

template<class VectorType>
BlockVectorBase& BlockVectorBase< VectorType >::operator*= ( const value_type  factor)

Scale each element of the vector by a constant value.

template<class VectorType>
BlockVectorBase& BlockVectorBase< VectorType >::operator/= ( const value_type  factor)

Scale each element of the vector by the inverse of the given value.

template<class VectorType>
template<class BlockVector2 >
void BlockVectorBase< VectorType >::scale ( const BlockVector2 &  v)

Multiply each element of this vector by the corresponding element of v.

template<class VectorType>
template<class BlockVector2 >
void BlockVectorBase< VectorType >::equ ( const value_type  a,
const BlockVector2 &  V 
)

U=a*V. Assignment.

template<class VectorType>
void BlockVectorBase< VectorType >::equ ( const value_type  a,
const BlockVectorBase< VectorType > &  V,
const value_type  b,
const BlockVectorBase< VectorType > &  W 
)

U=a*V+b*W. Replacing by sum.

template<class VectorType>
void BlockVectorBase< VectorType >::update_ghost_values ( ) const

Update the ghost values by calling update_ghost_values for each block.

template<class VectorType>
std::size_t BlockVectorBase< VectorType >::memory_consumption ( ) const

Determine an estimate for the memory consumption (in bytes) of this object.

Friends And Related Function Documentation

template<class VectorType>
template<typename N , bool C>
friend class ::internal::BlockVectorIterators::Iterator
friend

Make the iterator class a friend.

Definition at line 954 of file block_vector_base.h.

Member Data Documentation

template<class VectorType>
std::vector<VectorType> BlockVectorBase< VectorType >::components
protected

Pointer to the array of components.

Definition at line 942 of file block_vector_base.h.

template<class VectorType>
BlockIndices BlockVectorBase< VectorType >::block_indices
protected

Object managing the transformation between global indices and indices within the different blocks.

Definition at line 948 of file block_vector_base.h.


The documentation for this class was generated from the following file: