Reference documentation for deal.II version 9.3.3
LinearAlgebra::CUDAWrappers::Vector< Number > Class Template Reference

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

Inheritance diagram for LinearAlgebra::CUDAWrappers::Vector< Number >:
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## Public Types

using value_type = typename VectorSpaceVector< Number >::value_type

using size_type = typename VectorSpaceVector< Number >::size_type

using real_type = typename VectorSpaceVector< Number >::real_type

## Public Member Functions

Vector ()

Vector (const Vector< Number > &V)

Vector (Vector< Number > &&) noexcept=default

Vector (const size_type n)

Vectoroperator= (const Vector< Number > &v)

Vectoroperator= (Vector< Number > &&v) noexcept=default

virtual void swap (Vector< Number > &v)

void reinit (const size_type n, const bool omit_zeroing_entries=false)

virtual void reinit (const VectorSpaceVector< Number > &V, const bool omit_zeroing_entries=false) override

virtual void import (const ReadWriteVector< Number > &V, VectorOperation::values operation, std::shared_ptr< const Utilities::MPI::CommunicationPatternBase > communication_pattern={}) override

virtual Vector< Number > & operator= (const Number s) override

virtual Vector< Number > & operator*= (const Number factor) override

virtual Vector< Number > & operator/= (const Number factor) override

virtual Vector< Number > & operator+= (const VectorSpaceVector< Number > &V) override

virtual Vector< Number > & operator-= (const VectorSpaceVector< Number > &V) override

virtual Number operator* (const VectorSpaceVector< Number > &V) const override

virtual void add (const Number a) override

virtual void add (const Number a, const VectorSpaceVector< Number > &V) override

virtual void add (const Number a, const VectorSpaceVector< Number > &V, const Number b, const VectorSpaceVector< Number > &W) override

virtual void sadd (const Number s, const Number a, const VectorSpaceVector< Number > &V) override

virtual void scale (const VectorSpaceVector< Number > &scaling_factors) override

virtual void equ (const Number a, const VectorSpaceVector< Number > &V) override

virtual bool all_zero () const override

virtual value_type mean_value () const override

virtual real_type l1_norm () const override

virtual real_type l2_norm () const override

real_type norm_sqr () const

virtual real_type linfty_norm () const override

virtual Number add_and_dot (const Number a, const VectorSpaceVector< Number > &V, const VectorSpaceVector< Number > &W) override

Number * get_values () const

virtual size_type size () const override

virtual ::IndexSet locally_owned_elements () const override

virtual void print (std::ostream &out, const unsigned int precision=2, const bool scientific=true, const bool across=true) const override

virtual std::size_t memory_consumption () const override

virtual void compress (VectorOperation::values)

## Static Public Member Functions

static ::ExceptionBaseExcVectorTypeNotCompatible ()

## Private Attributes

std::unique_ptr< Number[], void(*)(Number *)> val

size_type n_elements

## Detailed Description

template<typename Number>
class LinearAlgebra::CUDAWrappers::Vector< Number >

This class implements a vector using CUDA for use on Nvidia GPUs. This class is derived from the LinearAlgebra::VectorSpaceVector class.

Note
Only float and double are supported.
CUDAWrappers

Definition at line 55 of file cuda_vector.h.

## ◆ value_type

template<typename Number >
 using LinearAlgebra::CUDAWrappers::Vector< Number >::value_type = typename VectorSpaceVector::value_type

Definition at line 58 of file cuda_vector.h.

## ◆ size_type

template<typename Number >
 using LinearAlgebra::CUDAWrappers::Vector< Number >::size_type = typename VectorSpaceVector::size_type

Definition at line 59 of file cuda_vector.h.

## ◆ real_type

template<typename Number >
 using LinearAlgebra::CUDAWrappers::Vector< Number >::real_type = typename VectorSpaceVector::real_type

Definition at line 60 of file cuda_vector.h.

## ◆ Vector() [1/4]

template<typename Number >
 LinearAlgebra::CUDAWrappers::Vector< Number >::Vector ( )

Constructor. Create a vector of dimension zero.

## ◆ Vector() [2/4]

template<typename Number >
 LinearAlgebra::CUDAWrappers::Vector< Number >::Vector ( const Vector< Number > & V )

Copy constructor.

## ◆ Vector() [3/4]

template<typename Number >
 LinearAlgebra::CUDAWrappers::Vector< Number >::Vector ( Vector< Number > && )
defaultnoexcept

Move constructor.

## ◆ Vector() [4/4]

template<typename Number >
 LinearAlgebra::CUDAWrappers::Vector< Number >::Vector ( const size_type n )
explicit

Constructor. Set dimension to n and initialize all elements with zero.

The constructor is made explicit to avoid accident like this: v=0;. Presumably, the user wants to set every elements of the vector to zero, but instead, what happens is this call: v=Vector<Number>(0);, i.e. the vector is replaced by one of length zero.

## ◆ operator=() [1/3]

template<typename Number >
 Vector & LinearAlgebra::CUDAWrappers::Vector< Number >::operator= ( const Vector< Number > & v )

Copy assignment operator.

## ◆ operator=() [2/3]

template<typename Number >
 Vector & LinearAlgebra::CUDAWrappers::Vector< Number >::operator= ( Vector< Number > && v )
defaultnoexcept

Move assignment operator.

## ◆ swap()

template<typename Number >
 void Vector< Number >::swap ( Vector< Number > & v )
inlinevirtual

Swap the contents of this vector and the other vector v. One could do this operation with a temporary variable and copying over the data elements, but this function is significantly more efficient since it only swaps the pointers to the data of the two vectors and therefore does not need to allocate temporary storage and move data around.

This function is analogous to the swap function of all C++ standard containers. Also, there is a global function swap(u,v) that simply calls u.swap(v), again in analogy to standard functions.

This function is virtual in order to allow for derived classes to handle memory separately.

Definition at line 398 of file cuda_vector.h.

## ◆ reinit() [1/2]

template<typename Number >
 void LinearAlgebra::CUDAWrappers::Vector< Number >::reinit ( const size_type n, const bool omit_zeroing_entries = false )

Reinit functionality. The flag omit_zeroing_entries determines whether the vector should be filled with zero (false) or left untouched (true).

## ◆ reinit() [2/2]

template<typename Number >
 virtual void LinearAlgebra::CUDAWrappers::Vector< Number >::reinit ( const VectorSpaceVector< Number > & V, const bool omit_zeroing_entries = false )
overridevirtual

Change the dimension to that of the vector V. The elements of V are not copied.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ import()

template<typename Number >
 virtual void LinearAlgebra::CUDAWrappers::Vector< Number >::import ( const ReadWriteVector< Number > & V, VectorOperation::values operation, std::shared_ptr< const Utilities::MPI::CommunicationPatternBase > communication_pattern = {} )
overridevirtual

Import all the element from the input vector V. VectorOperation::values operation is used to decide if the elements int V should be added to the current vector or replace the current elements. The last parameter is not used. It is only used for distributed vectors. This is the function that should be used to copy a vector to the GPU.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ operator=() [3/3]

template<typename Number >
 virtual Vector< Number > & LinearAlgebra::CUDAWrappers::Vector< Number >::operator= ( const Number s )
overridevirtual

Sets all elements of the vector to the scalar s. This operation is only allowed if s is equal to zero.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ operator*=()

template<typename Number >
 virtual Vector< Number > & LinearAlgebra::CUDAWrappers::Vector< Number >::operator*= ( const Number factor )
overridevirtual

Multiply the entive vector by a fixed factor.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ operator/=()

template<typename Number >
 virtual Vector< Number > & LinearAlgebra::CUDAWrappers::Vector< Number >::operator/= ( const Number factor )
overridevirtual

Divide the entire vector by a fixed factor.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ operator+=()

template<typename Number >
 virtual Vector< Number > & LinearAlgebra::CUDAWrappers::Vector< Number >::operator+= ( const VectorSpaceVector< Number > & V )
overridevirtual

Add the vector V to the present one.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ operator-=()

template<typename Number >
 virtual Vector< Number > & LinearAlgebra::CUDAWrappers::Vector< Number >::operator-= ( const VectorSpaceVector< Number > & V )
overridevirtual

Subtract the vector V from the present one.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ operator*()

template<typename Number >
 virtual Number LinearAlgebra::CUDAWrappers::Vector< Number >::operator* ( const VectorSpaceVector< Number > & V ) const
overridevirtual

Return the scalar product of two vectors.

Implements LinearAlgebra::VectorSpaceVector< Number >.

template<typename Number >
 virtual void LinearAlgebra::CUDAWrappers::Vector< Number >::add ( const Number a )
overridevirtual

Add to all components. Note that a is a scalar not a vector.

Implements LinearAlgebra::VectorSpaceVector< Number >.

template<typename Number >
 virtual void LinearAlgebra::CUDAWrappers::Vector< Number >::add ( const Number a, const VectorSpaceVector< Number > & V )
overridevirtual

Simple addition of a multiple of a vector, i.e. *this += a*V.

Implements LinearAlgebra::VectorSpaceVector< Number >.

template<typename Number >
 virtual void LinearAlgebra::CUDAWrappers::Vector< Number >::add ( const Number a, const VectorSpaceVector< Number > & V, const Number b, const VectorSpaceVector< Number > & W )
overridevirtual

Multiple additions of scaled vectors, i.e. *this += a*V+b*W.

Implements LinearAlgebra::VectorSpaceVector< Number >.

template<typename Number >
 virtual void LinearAlgebra::CUDAWrappers::Vector< Number >::sadd ( const Number s, const Number a, const VectorSpaceVector< Number > & V )
overridevirtual

Scaling and simple addition of a multiple of a vector, i.e. this = s(*this)+a*V

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ scale()

template<typename Number >
 virtual void LinearAlgebra::CUDAWrappers::Vector< Number >::scale ( const VectorSpaceVector< Number > & scaling_factors )
overridevirtual

Scale each element of this vector by the corresponding element in the argument. This function is mostly meant to simulate multiplication (and immediate re-assignment) by a diagonal scaling matrix.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ equ()

template<typename Number >
 virtual void LinearAlgebra::CUDAWrappers::Vector< Number >::equ ( const Number a, const VectorSpaceVector< Number > & V )
overridevirtual

Assignment *this = a*V.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ all_zero()

template<typename Number >
 virtual bool LinearAlgebra::CUDAWrappers::Vector< Number >::all_zero ( ) const
overridevirtual

Return whether the vector contains only elements with value zero.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ mean_value()

template<typename Number >
 virtual value_type LinearAlgebra::CUDAWrappers::Vector< Number >::mean_value ( ) const
overridevirtual

Return the mean value of all the entries of this vector.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ l1_norm()

template<typename Number >
 virtual real_type LinearAlgebra::CUDAWrappers::Vector< Number >::l1_norm ( ) const
overridevirtual

Return the l1 norm of the vector (i.e., the sum of the absolute values of all entries among all processors).

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ l2_norm()

template<typename Number >
 virtual real_type LinearAlgebra::CUDAWrappers::Vector< Number >::l2_norm ( ) const
overridevirtual

Return the l2 norm of the vector (i.e., the square root of the sum of the square of all entries among all processors).

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ norm_sqr()

template<typename Number >
 real_type LinearAlgebra::CUDAWrappers::Vector< Number >::norm_sqr ( ) const

Return the square of the $$l_2$$-norm.

## ◆ linfty_norm()

template<typename Number >
 virtual real_type LinearAlgebra::CUDAWrappers::Vector< Number >::linfty_norm ( ) const
overridevirtual

Return the maximum norm of the vector (i.e., the maximum absolute value among all entries and among all processors).

Implements LinearAlgebra::VectorSpaceVector< Number >.

template<typename Number >
 virtual Number LinearAlgebra::CUDAWrappers::Vector< Number >::add_and_dot ( const Number a, const VectorSpaceVector< Number > & V, const VectorSpaceVector< Number > & W )
overridevirtual

Perform 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

return_value = *this * W;
virtual void add(const Number a) override
static const char V

The reason this function exists is that this operation involves less memory transfer than calling the two functions separately. 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).

For complex-valued vectors, the scalar product in the second step is implemented as $$\left<v,w\right>=\sum_i v_i \bar{w_i}$$.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ get_values()

template<typename Number >
 Number * Vector< Number >::get_values
inline

Return the pointer to the underlying array. Ownership still resides with this class.

Definition at line 372 of file cuda_vector.h.

## ◆ size()

template<typename Number >
 Vector< Number >::size_type Vector< Number >::size
inlineoverridevirtual

Return the size of the vector.

Implements LinearAlgebra::VectorSpaceVector< Number >.

Definition at line 381 of file cuda_vector.h.

## ◆ locally_owned_elements()

template<typename Number >
 IndexSet Vector< Number >::locally_owned_elements
inlineoverridevirtual

Return an index set that describe which elements of this vector are owned by the current processor, i.e. [0, size).

Implements LinearAlgebra::VectorSpaceVector< Number >.

Definition at line 389 of file cuda_vector.h.

## ◆ print()

template<typename Number >
 virtual void LinearAlgebra::CUDAWrappers::Vector< Number >::print ( std::ostream & out, const unsigned int precision = 2, const bool scientific = true, const bool across = true ) const
overridevirtual

Print the vector to the output stream out.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ memory_consumption()

template<typename Number >
 virtual std::size_t LinearAlgebra::CUDAWrappers::Vector< Number >::memory_consumption ( ) const
overridevirtual

Return the memory consumption of this class in bytes.

Implements LinearAlgebra::VectorSpaceVector< Number >.

## ◆ val

template<typename Number >
 std::unique_ptr LinearAlgebra::CUDAWrappers::Vector< Number >::val
private

Pointer to the array of elements of this vector.

Definition at line 339 of file cuda_vector.h.

## ◆ n_elements

template<typename Number >
 size_type LinearAlgebra::CUDAWrappers::Vector< Number >::n_elements
private

Number of elements in the vector.

Definition at line 344 of file cuda_vector.h.

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