letter_to_pos¶
-
inline element_index_type libsemigroups::FroidurePinBase::letter_to_pos(letter_type i) const¶
Returns the position in
this
of the generator with indexi
.If
i
is not a valid generator index, a LibsemigroupsException will be thrown. In many casesletter_to_pos(i)
will equali
, examples of when this will not be the case are:there are duplicate generators;
FroidurePin::add_generators was called after the semigroup was already partially enumerated.