PermutationWrapper< _IndicesType > Class Template Reference

Detailed Description

template<typename _IndicesType>
class Eigen::PermutationWrapper< _IndicesType >

Class to view a vector of integers as a permutation matrix.

Parameters

_IndicesType

the type of the vector of integer (can be any compatible expression)

This class allows to view any vector expression of integers as a permutation matrix.

See also

class PermutationBase, class PermutationMatrix

Inheritance diagram for PermutationWrapper< _IndicesType >:

Public Member Functions
PermutationWrapper< _IndicesType > &	applyTranspositionOnTheLeft (Index i, Index j)
PermutationWrapper< _IndicesType > &	applyTranspositionOnTheRight (Index i, Index j)
Index	cols () const
PermutationWrapper< _IndicesType > &	derived ()
const PermutationWrapper< _IndicesType > &	derived () const
Index	determinant () const
IndicesType &	indices ()
const internal::remove_all< typenameIndicesType::Nested >::type &	indices () const
Transpose< PermutationBase >	inverse () const
PlainPermutationType	operator* (const PermutationBase< Other > &other) const
PlainPermutationType	operator* (const Transpose< PermutationBase< Other > > &other) const
void	resize (Index newSize)
Index	rows () const
void	setIdentity ()
void	setIdentity (Index newSize)
Index	size () const
DenseMatrixType	toDenseMatrix () const
Transpose< PermutationBase >	transpose () const

Member Function Documentation

applyTranspositionOnTheLeft()

PermutationWrapper< _IndicesType > & applyTranspositionOnTheLeft ( Index i, Index j )

inlineinherited

Multiplies *this by the transposition on the left.

Returns

a reference to *this.

Warning

This is much slower than applyTranspositionOnTheRight(int,int): this has linear complexity and requires a lot of branching.

See also

applyTranspositionOnTheRight(int,int)

applyTranspositionOnTheRight()

PermutationWrapper< _IndicesType > & applyTranspositionOnTheRight ( Index i, Index j )

inlineinherited

Multiplies *this by the transposition on the right.

Returns

a reference to *this.

This is a fast operation, it only consists in swapping two indices.

See also

applyTranspositionOnTheLeft(int,int)

cols()

Index cols ( ) const

inlineinherited

Returns

the number of columns

derived() [1/2]

PermutationWrapper< _IndicesType > & derived ( )

inlineinherited

Returns

a reference to the derived object

derived() [2/2]

const PermutationWrapper< _IndicesType > & derived ( ) const

inlineinherited

Returns

a const reference to the derived object

determinant()

Index determinant ( ) const

inlineinherited

Returns

the determinant of the permutation matrix, which is either 1 or -1 depending on the parity of the permutation.

This function is O(n) procedure allocating a buffer of n booleans.

indices() [1/2]

IndicesType & indices ( )

inlineinherited

Returns

a reference to the stored array representing the permutation.

indices() [2/2]

template<typename _IndicesType>

const internal::remove_all< typenameIndicesType::Nested >::type & indices ( ) const

inline

const version of indices().

inverse()

Transpose< PermutationBase > inverse ( ) const

inlineinherited

Returns

the inverse permutation matrix.

Note

This function returns the result by value. In order to make that efficient, it is implemented as just a return statement using a special constructor, hopefully allowing the compiler to perform a RVO (return value optimization).

operator*() [1/2]

PlainPermutationType operator* ( const PermutationBase< Other > & other ) const

inlineinherited

Returns

the product permutation matrix.

Note

This function returns the result by value. In order to make that efficient, it is implemented as just a return statement using a special constructor, hopefully allowing the compiler to perform a RVO (return value optimization).

operator*() [2/2]

PlainPermutationType operator* ( const Transpose< PermutationBase< Other > > & other ) const

inlineinherited

Returns

the product of a permutation with another inverse permutation.

Note

This function returns the result by value. In order to make that efficient, it is implemented as just a return statement using a special constructor, hopefully allowing the compiler to perform a RVO (return value optimization).

resize()

void resize ( Index newSize )

inlineinherited

Resizes to given size.

rows()

Index rows ( ) const

inlineinherited

Returns

the number of rows

setIdentity() [1/2]

void setIdentity ( )

inlineinherited

Sets *this to be the identity permutation matrix

setIdentity() [2/2]

void setIdentity ( Index newSize )

inlineinherited

Sets *this to be the identity permutation matrix of given size.

size()

Index size ( ) const

inlineinherited

Returns

the size of a side of the respective square matrix, i.e., the number of indices

toDenseMatrix()

DenseMatrixType toDenseMatrix ( ) const

inlineinherited

Returns

a Matrix object initialized from this permutation matrix. Notice that it is inefficient to return this Matrix object by value. For efficiency, favor using the Matrix constructor taking EigenBase objects.

transpose()

Transpose< PermutationBase > transpose ( ) const

inlineinherited

Returns

the tranpose permutation matrix.

Note

This function returns the result by value. In order to make that efficient, it is implemented as just a return statement using a special constructor, hopefully allowing the compiler to perform a RVO (return value optimization).

---

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

• PermutationMatrix.h