csl::Permutation Class Reference

Handles a std::vector of integers that represents the permutation of n indices, with a possible symmetry of an IndexStructure. More...

#include <symmetry.h>

Public Member Functions
	Permutation ()
	Default constructor.
	Permutation (int n)
	Initializes the identity permutation of n elements. More...
	Permutation (const std::vector< int > &t_permutation)
	constructor that takes a vector of integers corresponding to the permutation. All integers between 0 and the size of t_permutation-1 must be represented. More...
	Permutation (int n, const std::vector< int > &list)
	Constructor that initializes the size of the Permutation to n, and takes one cycle (that concerns possibly only few elements) as initialization. For example, Permutation(5,{1,0,2}) intializes the permutation to (2,0,1,3,4). More...
	Permutation (int n, const std::vector< int > &list, int sym)
	Permutation (int n, const std::vector< std::vector< int > > &list)
	Constructor that initializes the size of the Permutation to n, and takes several cycles (that concerns possibly only few elements) as initialization. For example Permutation(10,{{6,7},{1,0,2}}) initializes the permutation to (2,0,1,3,4,5,7,6,8,9). More...
	Permutation (const Permutation &permutation)=default
	Copy constructor. More...
	~Permutation ()
	Destructor.
int	getOrder ()
	This function calculates the order of the permutation the first time, or just return it if it has already been calculated. More...
int	getSign ()
	This function calculates the sign of the permutation the first time, or just return it if it has already been calculated. More...
int	getSymmetry () const
std::vector< int >	getPermutation () const
void	setSymmetry (int t_symmetry)
void	adjustToSize (size_t newSize)
void	applyRedefinition (const std::vector< size_t > &redefinition)
Permutation &	operator= (const Permutation &t_permutation)=default
	Assignement operator. Copies t_permutation and returns a reference to *this. More...
Permutation	operator* (const Permutation &t_permutation) const
	operator*, Compose two Permutation objects and returns the result in a new Permutation. More...
bool	operator== (const Permutation &t_permutation) const
	operator==, tells if two Permutation objects are equal. More...
bool	operator!= (const Permutation &t_permuation) const
	operator!=, tells if two Permutation objects are not equal. More...

Friends
std::ostream &	operator<< (std::ostream &fout, const Permutation &permutation)
	operator<<, displays the Permutation t_permutation in the output fout. More...

Detailed Description

Handles a std::vector of integers that represents the permutation of n indices, with a possible symmetry of an IndexStructure.

Constructor & Destructor Documentation

Permutation() [1/5]

csl::Permutation::Permutation ( int  n )

explicit

Initializes the identity permutation of n elements.

Parameters

n	The number of elements of the permutation.

Permutation() [2/5]

csl::Permutation::Permutation ( const std::vector< int > &  t_permutation )

explicit

constructor that takes a vector of integers corresponding to the permutation. All integers between 0 and the size of t_permutation-1 must be represented.

Parameters

t_permutation

The complete permutation in the form of a std::vector<int>.

Permutation() [3/5]

csl::Permutation::Permutation	(	int	n,
		const std::vector< int > &	list
	)

Constructor that initializes the size of the Permutation to n, and takes one cycle (that concerns possibly only few elements) as initialization. For example, Permutation(5,{1,0,2}) intializes the permutation to (2,0,1,3,4).

Parameters

n	Total size of the permutation.
list	Only cycle in the permutation.

Permutation() [4/5]

csl::Permutation::Permutation	(	int	n,
		const std::vector< std::vector< int > > &	list
	)

Constructor that initializes the size of the Permutation to n, and takes several cycles (that concerns possibly only few elements) as initialization. For example Permutation(10,{{6,7},{1,0,2}}) initializes the permutation to (2,0,1,3,4,5,7,6,8,9).

Parameters

n	Total size of the permutation.
list	Cycles in the permutation.

Here just test of validity of the cycle

Permutation() [5/5]

csl::Permutation::Permutation ( const Permutation &  permutation )

default

Copy constructor.

Parameters

permutation

Permutation to copy.

Member Function Documentation

getOrder()

int csl::Permutation::getOrder

(

)

This function calculates the order of the permutation the first time, or just return it if it has already been calculated.

Returns

The order of the permutation.

getPermutation()

vector< int > csl::Permutation::getPermutation

(

)

const

Returns

The vector of integers defining the permutation.

getSign()

int csl::Permutation::getSign

(

)

This function calculates the sign of the permutation the first time, or just return it if it has already been calculated.

Returns

The sign of the permutation.

getSymmetry()

int csl::Permutation::getSymmetry

(

)

const

Returns

The symmetry factor the user associated with the permutation, (1 if symmetric -1 if antisymmetric).

operator!=()

bool csl::Permutation::operator!=

(

const Permutation &

t_permuation

)

const

operator!=, tells if two Permutation objects are not equal.

Parameters

t_permutation

Permutation to compare to *this.

Returns

False if the two Permutation objects are equal.

True else.

operator*()

Permutation csl::Permutation::operator*

(

const Permutation &

t_permutation

)

const

operator*, Compose two Permutation objects and returns the result in a new Permutation.

Parameters

t_permutation

Permutation to multiply to *this.

Returns

A Permutation that is the product of *this and t_permutation.

operator=()

Permutation& csl::Permutation::operator= ( const Permutation &  t_permutation )

default

Assignement operator. Copies t_permutation and returns a reference to *this.

Parameters

t_permutation

Permutation to copy.

Returns

A reference to the modified object.

operator==()

bool csl::Permutation::operator==

(

const Permutation &

t_permutation

)

const

operator==, tells if two Permutation objects are equal.

Parameters

t_permutation

Permutation to compare to *this.

Returns

True if the two Permutation objects are equal.

False else.

setSymmetry()

void csl::Permutation::setSymmetry

(

int

t_symmetry

)

Parameters

t_symmetry

New symmetry factor, =1 if symmetric, =-1 if antisymmetric.

Friends And Related Function Documentation

operator<<

std::ostream& operator<< ( std::ostream &  fout, const Permutation &  permutation  )

friend

operator<<, displays the Permutation t_permutation in the output fout.

Parameters

fout	Output flux.
permutation	Permutation to diplay.

Returns

A reference to the modified flux fout.

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

• include/symmetry.h
• src/symmetry.cpp