Notes on computational linguistics.pdf - UCLA Department of ...

Stabler - Lx 185/209 2003
1 ?- [col12].
% col12 compiled 2.13 sec, 52 bytes
Yes
2 ?- tell(’col12r.pl’),lex(Word,[B|C]),atom_chars(Word,Chars),
portray_clause(lex(B,C,Chars)),fail;told.
No
You do not need to know about the special prolog facilities that are used here, but in case you are interested,
here is a quick explanation.
The built-in command tell causes all output to be written to the specified file; then each clause of lex is
written in the new format using the built-in command portray_clause – which is just like write except that
its argument is followed by a period, etc. so that it can be read as a clause; then the fail causes the prolog to
backtrack an find the next clause, and the next and so on, until all of them are found. When all ways of proving
the first conjuncts fail, then the built-in command told closes the file that was opened by tell and succeeds.
After executing this command, we have a new representation of the lexicon that has clauses like this in it:
...
lex(&, [d, m, @, r, @, l, t, ’I’], [a, d, m, i, r, a, l, t, y]).
lex(&, [d, m, @, r, eI, ’S’, n], [a, d, m, i, r, a, t, i, o, n]).
lex(@, [d, m, aI, @, ’R’], [a, d, m, i, r, e]).
lex(@, [d, m, aI, @, d], [a, d, m, i, r, e, d]).
lex(@, [d, m, aI, r, @, ’R’], [a, d, m, i, r, e, r]).
lex(@, [d, m, aI, r, @, z], [a, d, m, i, r, e, r, s]).
lex(@, [d, m, aI, @, z], [a, d, m, i, r, e, s]).
lex(@, [d, m, aI, @, r, ’I’, ’N’], [a, d, m, i, r, i, n, g]).
lex(@, [d, m, aI, @, r, ’I’, ’N’, l, ’I’], [a, d, m, i, r, i, n, g, l, y]).
lex(@, [d, m, ’I’, s, @, b, ’I’, l, ’I’, t, ’I’], [a, d, m, i, s, s, i, b, i, l, i, t, y]).
lex(@, [d, m, ’I’, s, @, b, l], [a, d, m, i, s, s, i, b, l, e]).
lex(@, [d, m, ’I’, ’S’, n], [a, d, m, i, s, s, i, o, n]).
lex(@, [d, m, ’I’, ’S’, n, z], [a, d, m, i, s, s, i, o, n, s]).
lex(@, [d, m, ’I’, t], [a, d, m, i, t]).
lex(@, [d, m, ’I’, t, s], [a, d, m, i, t, s]).
lex(@, [d, m, ’I’, t, n, s], [a, d, m, i, t, t, a, n, c, e]).
...
This lexicon is more efficiently accessed because the first symbol of the phonetic transcription is exposed as
the first argument.
We just need to modify slightly the translate program to use this new representation of the dictionary:
%File: medprog.pl
% first, we load the first 2 columns of the Mitton lexicon in the new format
:- [col12r].
%translate(Phones,Words)
translate([],[]).
translate(Phones,[Word|Words]) :append([First|MorePhones],RestPhones,Phones),
%% minor change here
lex(First,MorePhones,Chars), %% minor change here
atom_chars(Word,Chars),
translate(RestPhones,Words).
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