CongruenceInterface¶

class CongruenceInterface : public libsemigroups::Runner ¶

Defined in cong-intf.hpp.

Every class for representing congruences in libsemigroups is derived from CongruenceInterface, which holds the member functions that are common to all its derived classes. CongruenceInterface is an abstract class.

Subclassed by libsemigroups::CongruenceByPairs< FroidurePin< detail::KBE, FroidurePinTraits< detail::KBE, fpsemigroup::KnuthBendix > > >, libsemigroups::Congruence, libsemigroups::CongruenceByPairs< TFroidurePinType >, libsemigroups::congruence::Kambites, libsemigroups::congruence::KnuthBendix, libsemigroups::congruence::ToddCoxeter

Member types¶

`class_index_type`	Type for indices of congruence class indices.
`const_iterator`	Type for a `const_iterator` to the generating pairs.
`non_trivial_class_iterator`	Type for a `const_iterator` to non-trivial classes.
`non_trivial_classes_type`	Type for non-trivial classes.

Constructors¶

`CongruenceInterface(CongruenceInterface const&) = default`	Default copy constructor.
`CongruenceInterface(congruence_kind)`	Constructs a congruence of the specified type.

Deleted constructors¶

`CongruenceInterface() = delete`	Deleted.
`CongruenceInterface(CongruenceInterface&&) = delete`	Deleted.
`operator=(CongruenceInterface const&) = delete`	Deleted.
`operator=(CongruenceInterface&&) = delete`	Deleted.

Initialization¶

`add_pair(std::initializer_list<size_t>, std::initializer_list<size_t>)`	Add a generating pair to the congruence.
`add_pair(word_type const&, word_type const&)`	Add a generating pair to the congruence.
`number_of_generating_pairs() const noexcept`	The number of generating pairs.
`number_of_generators() const noexcept`	The number of generators.
`set_number_of_generators(size_t)`	Set the number of generators of the congruence.

Handedness¶

kind() const noexcept

The handedness of the congruence (left, right, or 2-sided).

Iterators¶

`cbegin_generating_pairs() const noexcept`	Returns a const iterator pointing to the first generating pair.
`cbegin_ntc()`	Returns a const iterator pointing to the first non-singleton class.
`cend_generating_pairs() const noexcept`	Returns a const iterator pointing one-after-the-end of the last generating pair.
`cend_ntc()`	Returns a const iterator pointing one-past-the-end of the last non-singleton class.

Words and class indices¶

`class_index_to_word(class_index_type)`	Get a canonical representative of the `i-th` class.
`word_to_class_index(word_type const&)`	Convert a word into the index of the class containing it.

Numbers of classes, and comparisons¶

`const_contains(word_type const&, word_type const&) const`	Check if a pair of words is known to belong to the congruence.
`contains(word_type const&, word_type const&)`	Check if a pair of words belongs to the congruence.
`less(word_type const&, word_type const&)`	Compare the indices of the classes containing two words.
`non_trivial_classes()`	Returns a shared pointer to the non-trivial classes.
`number_of_classes()`	Compute the number of classes in the congruence.
`number_of_non_trivial_classes()`	The number of non-singleton classes.

Member functions inherited from Runner¶

`dead() const noexcept`	Check if the runner is dead.
`finished() const`	Check if `run` has been run to completion or not.
`kill() noexcept`	Stop `run` from running (thread-safe).
`report() const`	Check if it is time to report.
`report_every() const noexcept`	Get the minimum elapsed time between reports.
`report_every(TIntType)`	Set the minimum elapsed time between reports.
`report_every(std::chrono::nanoseconds)`	Set the minimum elapsed time between reports.
`report_why_we_stopped() const`	Report why `run` stopped.
`run()`	Run until `finished` .
`run_for(TIntType)`	Run for a specified amount of time.
`run_for(std::chrono::nanoseconds)`	Run for a specified amount of time.
`run_until(T&&)`	Run until a nullary predicate returns `true` or `finished` .
`run_until(bool(*)())`	Run until a nullary predicate returns `true` or `finished` .
`running() const noexcept`	Check if currently running.
`running_for() const noexcept`	Check if the runner is currently running for a particular length of time.
`running_until() const noexcept`	Check if the runner is currently running until a nullary predicate returns `true`.
`started() const`	Check if `run` has been called at least once before.
`stopped() const`	Check if the runner is stopped.
`stopped_by_predicate() const`	Check if the runner was, or should, stop because of the argument for `run_until` .
`timed_out() const`	Check if the amount of time passed to `run_for` has elapsed.

`has_parent_fpsemigroup() const noexcept`	Check if the congruence was constructed from a `FpSemigroupInterface` instance.
`has_parent_froidure_pin() const noexcept`	Check if the congruence was constructed from a `FroidurePin` instance.
`has_quotient_froidure_pin() const noexcept`	Check if the quotient semigroup has been computed.
`is_quotient_obviously_finite()`	Deterministically check if the quotient is finite.
`is_quotient_obviously_infinite()`	Deterministically check if the quotient is infinite.
`parent_fpsemigroup() const`	Get the parent `FpSemigroupInterface` instance (if any).
`parent_froidure_pin() const`	Get the parent `FroidurePin` instance (if any).
`quotient_froidure_pin()`	Returns a semigroup represented as an instance of a derived class of `FroidurePinBase` that is isomorphic to the quotient of the parent semigroup of `this` by the 2-sided congruence that `this` represents.