Aspekte der morphologischen Analyse des Deutschen - Universität ...

Anhang C: Programmcode
/*********************************************************************************************************************************
process_lex_entries/0:
Adds all lexicon entries to the automation and constructs
the failure function afterwards
*********************************************************************************************************************************/
process_lex_entries :-
(--->(Word,_Desc)), % extract lexicon entry
\+ (Word = unknown(_W)), % special entry 'unknown' isn't inserted
add_to_automation(Word), % insert Word into the automation
fail.
process_lex_entries.
/*********************************************************************************************************************************
startstate_completition/0:
adds a transition for all symbols from startstate to startstate for
which no transition is defined yet
*********************************************************************************************************************************/
startstate_completition :-
automation_alphabet(Alphabet),
startstate(Start),
add_start_transitions(Alphabet,Start).
add_start_transitions([],_Start).
add_start_transitions([AlphabetSymbol|RestAlphabet],Start) :-
transition(Start,AlphabetSymbol,State),
((State = fail) ->
add_transition(Start,AlphabetSymbol,Start)
;
true % a transition is already there, so do nothing
),
add_start_transitions(RestAlphabet,Start).
/*********************************************************************************************************************************
construct_failure_function/0:
constructs the failure function of the segmentizer.
*********************************************************************************************************************************/
construct_failure_function :-
automation_alphabet(Alphabet),
startstate(Start),
make_queue(Queue),
% initialize the queue
queue_startstates(Alphabet,Start,Queue,NewQueue),
process_queue(NewQueue,Alphabet).
/*********************************************************************************************************************************
queue_startstates(Alphabet:,Start:,Queue1,Queue2):
Adds all states to Queue for which there are transitions to a state not equal
to Start
*********************************************************************************************************************************/
queue_startstates([],_Start,Queue,Queue).
queue_startstates([AlphabetSymbol|RestAlphabet],Start,Queue0,Queue) :-
transition(Start,AlphabetSymbol,NewState), % should never fail
((NewState = Start) ->
Queue1 = Queue0
;
( enqueue(NewState,Queue0,Queue1),
assert(f(NewState,Start))
)),
queue_startstates(RestAlphabet,Start,Queue1,Queue).
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