Butterfly Class Template Reference
[linbox/blackbox]

#include <butterfly.h>

Inheritance diagram for Butterfly:

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Detailed Description

template<class _Field, class Switch>
class LinBox::Butterfly< _Field, Switch >

Switching Network based BlackBox Matrix. A good preconditioner.

Implements butterfly switching network on a LinBox vector as a black box matrix through the use of a switch object.

This is a blackbox matrix object, and it implements all purely virtual methods of the abstract base class. See {BlackboxArchetype} for the specification of these methods.

This matrix requires a dense vector to be used. Sparse vectors must somehow be converted to dense vectors before this matrix may be applied to them.

Parameters:

	Vector	LinBox dense vector type
	Switch	switch object type

Butterfly
Butterfly preconditioner and supporting function
	Butterfly (const Field &F, size_t n, typename Switch::Factory &factory)
template<class OutVector, class InVector> OutVector &	apply (OutVector &y, const InVector &x) const
template<class OutVector, class InVector> OutVector &	applyTranspose (OutVector &y, const InVector &x) const
Public Types
typedef _Field	Field
typedef Field::Element	Element
Public Member Functions
	~Butterfly ()
size_t	rowdim () const
size_t	coldim () const
const Field &	field () const

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Member Typedef Documentation

typedef _Field Field

typedef Field::Element Element

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Constructor & Destructor Documentation

Butterfly (  const Field &  F, size_t  n, typename Switch::Factory &  factory )  [inline]

Constructor from an integer and a switch object. The switch object is an object that is applied to two references to elements to switch them. It must have both an apply and an applyTranspose method. It must contain all information needed by the switch other than the elements themselves. This includes any random numbers or sequences of values. It must also be able to be applied as many times as needed. In particular, it must be able to create new random elements or repeat a stored sequence of values. This is not required by the abstract base class. Parameters: n  integer size of vectors to be applied to S  switch predicate object object

~Butterfly (   )  [inline]

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Member Function Documentation

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

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

size_t rowdim (   )  const [inline]

size_t coldim (   )  const [inline]

const Field& field (   )  const [inline]

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