permlib::Permutation Class Reference

Permutation class storing all values explicitly. More...

#include <permutation.h>

List of all members.

Public Types
typedef std::vector< dom_int >	perm
	typedef for permutation image
typedef boost::shared_ptr < Permutation >	ptr
	boost shared_ptr of this class
Public Member Functions
	Permutation (dom_int n)
	constructs identity permutation acting on n elements
	Permutation (dom_int n, const std::string &cycles)
	constructs permutation acting on n elements, given by string in cycle form
	Permutation (dom_int n, const char *cycles)
	constructs permutation acting on n elements, given by string in cycle form
	Permutation (const perm &p)
	sort of copy constructor
	Permutation (const Permutation &p)
	copy constructor
template<class InputIterator >
	Permutation (InputIterator begin, InputIterator end)
	construct from dom_int-iterator
Permutation	operator* (const Permutation &p) const
	permutation multiplication from the right
Permutation &	operator*= (const Permutation &p)
	permutation inplace multiplication from the right
Permutation &	operator^= (const Permutation &p)
	permutation inplace multiplication from the left
Permutation	operator~ () const
	permutation inversion
Permutation &	invertInplace ()
	permutation inplace inversion
bool	operator== (const Permutation &p2) const
	equals operator
dom_int	operator/ (dom_int val) const
	lets permutation act on val
dom_int	at (dom_int val) const
	lets permutation act on val
dom_int	operator% (dom_int val) const
	lets inverse permutation act on val, i.e. compute j such that (this->at(j) == val)
bool	isIdentity () const
	returns true if this permutation is identity
void	flush ()
	dummy stub for interface compatability with PermutationWord
dom_int	size () const
	number of points this permutation acts on
std::list< std::pair< dom_int, unsigned int > >	cycles (bool includeTrivialCycles=false) const
	computes all cycles of this permutation
boost::uint64_t	order () const
	computes the order of this permutation
template<typename ForwardIterator >
Permutation *	project (unsigned int n_proj, ForwardIterator begin, ForwardIterator end) const
	restricts this permutation p to a subset S of the domain
void	setTransposition (dom_int pos, dom_int val)
	updates this permutation such that pos is mapped onto val and val onto pos
Protected Member Functions
	Permutation (dom_int n, bool)
	INTERNAL ONLY: constructs an "empty" permutation, i.e. without element mapping.
void	initFromCycleString (const std::string &cycles)
	initializes permutation data from a string in cycle form
Protected Attributes
perm	m_perm
	defintion of permutation behavior
bool	m_isIdentity
	if set to true, permutation is identity; if set to false then it is not known whether this is identity;
Friends
struct	permlib::exports::BSGSSchreierExport
std::ostream &	operator<< (std::ostream &out, const Permutation &p)
	output in cycle form

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Detailed Description

Permutation class storing all values explicitly.

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Member Function Documentation

std::list< std::pair< dom_int, unsigned int > > permlib::Permutation::cycles

(

bool

includeTrivialCycles = false

)

const [inline]

computes all cycles of this permutation

Parameters:

includeTrivialCycles

if true, the result list contains also cycles consisting of one single element

Returns:

list of pairs [minimal element of cycle, cycle length]

bool permlib::Permutation::isIdentity

(

)

const [inline]

returns true if this permutation is identity

This is done by checking the image of every point.

Permutation & permlib::Permutation::operator*=

(

const Permutation &

p

)

[inline]

permutation inplace multiplication from the right

i.e. THIS := THIS * p

Permutation & permlib::Permutation::operator^=

(

const Permutation &

p

)

[inline]

permutation inplace multiplication from the left

i.e. THIS := p * THIS

boost::uint64_t permlib::Permutation::order

(

)

const [inline]

computes the order of this permutation

Returns:

number c such that p^c = identity

template<typename ForwardIterator >

Permutation * permlib::Permutation::project	(	unsigned int	n_proj,
		ForwardIterator	begin,
		ForwardIterator	end
	)		const

restricts this permutation p to a subset S of the domain

S must fullfill S^p = S

Parameters:

n_proj	degree of the restricted permutation (ie. number of elements in the subset S
begin	begin-iterator to subset S
end	end-iterator to subset S

Returns:

pointer to a permutation which is restricted to the given domain subset

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

• include/permlib/permutation.h