Stephen¶

class Stephen : public libsemigroups::Runner ¶

Defined in stephen.hpp.

On this page we describe the functionality in libsemigroups relating to Stephen’s procedure for finitely presented semigroups. This class implements Stephen’s procedure for (possibly) constructing the word graph (ActionDigraph) corresponding to the left factors of a word in a finitely presented semigroup. The algorithm implemented in this class is closely related to the Todd-Coxeter algorithm (as implemented in congruence::ToddCoxeter) and originates in Applications of automata theory to presentations of monoids and inverse monoids by J. B. Stephen.

Member types¶

`digraph_type`	The return type of the function `word_graph` .
`node_type`	The type of the nodes of a `digraph_type` .

Constructor¶

`Stephen()`
`Stephen(P &&)`
`Stephen(Stephen &&) = default`	Default move constructor.
`Stephen(Stephen const &) = default`	Default copy constructor.
`operator=(Stephen &&) = default`	Default move assignment operator.
`operator=(Stephen const &) = default`	Default copy assignment operator.

Initialization¶

`init(P &&)`
`set_word(word_type &&)`
`set_word(word_type const &)`

Defining data¶

`presentation() const noexcept`
`word() const noexcept`

Results of the algorithm¶

`accept_state()`
`word_graph() const noexcept`

`dead() const noexcept`
`finished() const`
`kill() noexcept`
`report() const`
`report_every() const noexcept`
`report_every(TIntType)`
`report_every(std::chrono::nanoseconds)`
`report_why_we_stopped() const`
`run()`
`run_for(TIntType)`
`run_for(std::chrono::nanoseconds)`
`run_until(T&&)`
`run_until(bool(*)())`
`running() const noexcept`
`running_for() const noexcept`
`running_until() const noexcept`
`started() const`
`stopped() const`
`stopped_by_predicate() const`
`timed_out() const`