linbox
Public Member Functions
Compose< _Blackbox1, _Blackbox2 > Class Template Reference

Blackbox of a product: $C = AB$, i.e $Cx \gets A(Bx)$. More...

#include <compose.h>

Inherits BlackboxInterface.

Public Member Functions

 Compose (const Blackbox1 &A, const Blackbox2 &B)
 Constructor of C := A*B from blackbox matrices A and B. More...
 
 Compose (const Blackbox1 *A_ptr, const Blackbox2 *B_ptr)
 Constructor of C := (A_ptr)(*B_ptr). More...
 
 Compose (const Compose< Blackbox1, Blackbox2 > &Mat)
 Copy constructor. More...
 
 ~Compose ()
 Destructor.
 
template<class OutVector , class InVector >
OutVector & apply (OutVector &y, const InVector &x) const
 Matrix * column vector product. More...
 
template<class OutVector , class InVector >
OutVector & applyTranspose (OutVector &y, const InVector &x) const
 row vector * matrix product. More...
 
size_t rowdim (void) const
 The number of rows.
 
size_t coldim (void) const
 The number of columns.
 
const Field & field () const
 The field.
 
const Blackbox1 * getLeftPtr () const
 accessor to the blackboxes
 
const Blackbox2 * getRightPtr () const
 accessor to the blackboxes
 

Detailed Description

template<class _Blackbox1, class _Blackbox2>
class LinBox::Compose< _Blackbox1, _Blackbox2 >

Blackbox of a product: $C = AB$, i.e $Cx \gets A(Bx)$.

This is a class that multiplies two matrices by implementing an apply method that calls the apply methods of both of the consituent matrices, one after the other.

This class, like the Black Box archetype from which it is derived, is templatized by the vector type to which the matrix is applied. Both constituent matrices must also use this same vector type. For specification of the blackbox members see BlackboxArchetype.

Template parameter: must meet the vector requirement.General case

Examples:
examples/minpoly.C, examples/omp_block_rank.C, examples/smithsparse.C, and examples/valence.C.

Constructor & Destructor Documentation

◆ Compose() [1/3]

Compose ( const Blackbox1 &  A,
const Blackbox2 &  B 
)
inline

Constructor of C := A*B from blackbox matrices A and B.

Build the product A*B of any two black box matrices of compatible dimensions.

Precondition
A.coldim() == B.rowdim().
Parameters
Ablackbox
Bblackbox

◆ Compose() [2/3]

Compose ( const Blackbox1 *  A_ptr,
const Blackbox2 *  B_ptr 
)
inline

Constructor of C := (A_ptr)(*B_ptr).

This constructor creates a matrix that is a product of two black box matrices: A*B from pointers to them.

Parameters
A_ptrblackbox
B_ptrblackbox

◆ Compose() [3/3]

Compose ( const Compose< Blackbox1, Blackbox2 > &  Mat)
inline

Copy constructor.

Copies the composed matrix (a small handle). The underlying two matrices are not copied.

Parameters
[in]Matblackbox to copy.

Member Function Documentation

◆ apply()

OutVector& apply ( OutVector &  y,
const InVector &  x 
) const
inline

Matrix * column vector product.

$ y \gets (A\cdot B)\cdot x$ Applies B, then A.

Returns
reference to vector y containing output.
Parameters
xconstant reference to vector to contain input
[out]ythe result.

◆ applyTranspose()

OutVector& applyTranspose ( OutVector &  y,
const InVector &  x 
) const
inline

row vector * matrix product.

$ y \gets (A\cdot B)^t \cdot x$. Applies A^t then B^t.

Returns
reference to vector y containing output.
Parameters
xconstant reference to vector to contain input
[out]ythe result.

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