SimsRefinerIdeals

Defined in sims.hpp.

This class provides a pruner for pruning the search tree when looking for right or two-sided congruences arising from ideals (Rees congruences).

See also

pruners

add_pruner

Public Member Functions
	SimsRefinerIdeals ()
	Default constructor.
	SimsRefinerIdeals (Presentation< word_type > const &p)
	Construct from presentation.
	SimsRefinerIdeals (SimsRefinerIdeals &&that)
	Move constructor.
	SimsRefinerIdeals (SimsRefinerIdeals const &that)
	Copy constructor.
SimsRefinerIdeals &	init ()
	Reinitialize an existing SimsRefinerIdeals object.
SimsRefinerIdeals &	init (Presentation< word_type > const &p)
	Reinitialize an existing SimsRefinerIdeals object from a word_type presentation.
bool	operator() (Sims1::word_graph_type const &wg)
	Check if a word graph can be extended to one defining a Rees congruence.
SimsRefinerIdeals &	operator= (SimsRefinerIdeals &&that)
	Move assignment operator.
SimsRefinerIdeals &	operator= (SimsRefinerIdeals const &that)
	Copy assignment operator.
Presentation< word_type > const &	presentation () const noexcept
	Get the presentation over which the refiner is defined.

Constructor & Destructor Documentation

SimsRefinerIdeals()

SimsRefinerIdeals ( Presentation< word_type > const & p )

explicit

Constructs a SimsRefinerIdeals pruner for the semigroup or monoid defined by p.

Parameters

p	the presentation.

Exceptions

LibsemigroupsException	if p is not valid.
LibsemigroupsException	if p has 0-generators and 0-relations.
Libsemigroups	if the alphabet of p is not normalized.

Warning

This method assumes that KnuthBendix terminates on the input presentation p. If this is not the case, then this pruner may not terminate on certain inputs.

Member Function Documentation

init() [1/2]

SimsRefinerIdeals & init

(

)

This function puts an object back into the same state as if it had been newly default constructed.

Returns

A reference to *this.

init() [2/2]

SimsRefinerIdeals & init

(

Presentation< word_type > const &

p

)

This function puts an object back into the same state as if it had been newly constructed from the presentation p.

Parameters

p	the presentation.

Returns

A reference to *this.

Exceptions

LibsemigroupsException	if p is not valid.
LibsemigroupsException	if p has 0-generators and 0-relations.
Libsemigroups	if the alphabet of p is not normalized.

Warning

This function has no exception guarantee, the object will be in the same state as if it was default constructed if an exception is thrown.

This function assumes that KnuthBendix terminates on the input presentation p. If this is not the case, then the pruner may not terminate on certain inputs.

See also

presentation(Presentation<word_type> const&)

operator()()

bool operator() ( Sims1::word_graph_type const & wg )

nodiscard

Returns false if there is no way of adding edges and nodes to

wg

which will result in a word graph defining a Rees congruence. Otherwise returns true.

Warning

This method assumes that KnuthBendix terminates on the underlying presentation that was used to construct the SimsRefinerIdeals object. If this is not the case then th pruner may not terminate on certain inputs.

presentation()

Presentation< word_type > const & presentation ( ) const

inlinenodiscardnoexcept

Returns a const reference to the current relations of the underlying presentation.

This function returns the defining presentation of a SimsRefinerIdeals instance.

Returns

A const reference to Presentation<word_type>.

Exceptions

This function is noexcept and is guaranteed never to throw.

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

• /Users/jdm3/libsemigroups/include/libsemigroups/sims.hpp