dg::TriDiagonal< Container > Struct Template Reference

Fast (shared memory) tridiagonal sparse matrix. More...

Public Types
using	value_type = dg::get_value_type<Container>

Public Member Functions
	TriDiagonal ()=default
	TriDiagonal (unsigned size)
	Allocate size elements for M, O and P.
	TriDiagonal (Container M, Container O, Container P)
	Directly construct from M, O and P.
template<class Container2 >
	TriDiagonal (const TriDiagonal< Container2 > &other)
	Assign M, O, and P from other matrix.
unsigned	size () const
void	resize (unsigned size)
	Resize M, O, and P to given size.
void	operator() (const Container &x, Container &y) const
	Compute Matrix-vector product \(y = Tx\).
dg::IHMatrix_t< value_type >	asIMatrix () const
	convert to a sparse matrix format

Public Attributes
Container	M
	Subdiagonal ["Minus" -1] M[0] is ignored M[1] maps to T_10
Container	O
	Diagonal ["zerO" 0] O[0] maps to T_00
Container	P
	Uper diagonal ["Plus" +1] P[0] maps to T_01

Detailed Description

template<class Container>
struct dg::TriDiagonal< Container >

Fast (shared memory) tridiagonal sparse matrix.

Consists of the three diagonal vectors [M, O, P] (for "Minus" -1, "ZerO" 0, "Plus +1), i.e. M is the subdiagonal, O the diagonal and P the superdiagonal vector. \( M_0 \) and \( P_{N-1}\) are ignored

\[ T = \begin{pmatrix} O_0 & P_0 & & & & \\ M_1 & O_1 & P_1 & & & \\ & M_2 & O_2 & P_2 & & \\ & & M_3 & O_3 & P_3 & \\ & & &...& & \end{pmatrix}\]

Template Parameters

Container

One of the shared memory containers

See also

dg::mat::TridiagInvDF dg::mat::compute_Tinv_y

Member Typedef Documentation

value_type

template<class Container >

using dg::TriDiagonal< Container >::value_type = dg::get_value_type<Container>

Constructor & Destructor Documentation

TriDiagonal() [1/4]

template<class Container >

dg::TriDiagonal< Container >::TriDiagonal ( )

default

TriDiagonal() [2/4]

template<class Container >

dg::TriDiagonal< Container >::TriDiagonal ( unsigned size )

inline

Allocate size elements for M, O and P.

TriDiagonal() [3/4]

template<class Container >

dg::TriDiagonal< Container >::TriDiagonal ( Container M, Container O, Container P )

inline

Directly construct from M, O and P.

Parameters

M	Subdiagonal
O	Diagonal
P	Superdiagonal

TriDiagonal() [4/4]

template<class Container >

template<class Container2 >

dg::TriDiagonal< Container >::TriDiagonal ( const TriDiagonal< Container2 > & other )

inline

Assign M, O, and P from other matrix.

Template Parameters

Container2

Parameters

other

Member Function Documentation

asIMatrix()

template<class Container >

dg::IHMatrix_t< value_type > dg::TriDiagonal< Container >::asIMatrix ( ) const

inline

convert to a sparse matrix format

operator()()

template<class Container >

void dg::TriDiagonal< Container >::operator() ( const Container & x, Container & y ) const

inline

Compute Matrix-vector product \(y = Tx\).

Note

Implemented using dg::blas2::parallel_for (which only works on shared memory vectors)

Parameters

x	input
y	result

resize()

template<class Container >

void dg::TriDiagonal< Container >::resize ( unsigned size )

inline

Resize M, O, and P to given size.

Parameters

size

New size

size()

template<class Container >

unsigned dg::TriDiagonal< Container >::size ( ) const

inline

Member Data Documentation

M

template<class Container >

Container dg::TriDiagonal< Container >::M

Subdiagonal ["Minus" -1] M[0] is ignored M[1] maps to T_10

O

template<class Container >

Container dg::TriDiagonal< Container >::O

Diagonal ["zerO" 0] O[0] maps to T_00

P

template<class Container >

Container dg::TriDiagonal< Container >::P

Uper diagonal ["Plus" +1] P[0] maps to T_01

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

• topology/fem.h