Bug Summary

File:modules/base/pos.cc
Location:line 128, column 2
Description:Value stored to 'pd' is never read

Annotated Source Code

1/*************************************************************************/
2/* */
3/* Centre for Speech Technology Research */
4/* University of Edinburgh, UK */
5/* Copyright (c) 1996,1997 */
6/* All Rights Reserved. */
7/* */
8/* Permission is hereby granted, free of charge, to use and distribute */
9/* this software and its documentation without restriction, including */
10/* without limitation the rights to use, copy, modify, merge, publish, */
11/* distribute, sublicense, and/or sell copies of this work, and to */
12/* permit persons to whom this work is furnished to do so, subject to */
13/* the following conditions: */
14/* 1. The code must retain the above copyright notice, this list of */
15/* conditions and the following disclaimer. */
16/* 2. Any modifications must be clearly marked as such. */
17/* 3. Original authors' names are not deleted. */
18/* 4. The authors' names are not used to endorse or promote products */
19/* derived from this software without specific prior written */
20/* permission. */
21/* */
22/* THE UNIVERSITY OF EDINBURGH AND THE CONTRIBUTORS TO THIS WORK */
23/* DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING */
24/* ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT */
25/* SHALL THE UNIVERSITY OF EDINBURGH NOR THE CONTRIBUTORS BE LIABLE */
26/* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES */
27/* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN */
28/* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, */
29/* ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF */
30/* THIS SOFTWARE. */
31/* */
32/*************************************************************************/
33/* Author : Alan W Black */
34/* Date : August 1996 */
35/*-----------------------------------------------------------------------*/
36/* */
37/* Various part-of-speech predciting modules */
38/* */
39/*=======================================================================*/
40#include <cstdio>
41#include "festival.h"
42#include "lexicon.h"
43
44using namespace std;
45
46static EST_VTCandidate *pos_candlist(EST_Item *s,EST_Features &f);
47static EST_VTPath *pos_npath(EST_VTPath *p,EST_VTCandidate *c,EST_Features &f);
48static double find_np_prob(EST_VTPath *p,int n,int *state);
49
50static EST_Ngrammar *pos_ngram = 0;
51
52static EST_String zeroString("0");
53static int p_word = 0; // arbitrary numbers
54static int n_word = 1;
55
56LISP FT_Classic_POS_Utt(LISP utt)
57{
58 // Predict part of speech for word stream
59 EST_Utterance *u = get_c_utt(utt)(utterance(utt));
60 LISP pos_lex_name, pos_ngram_name;
61 LISP lastlex, pos_p_start_tag, pos_pp_start_tag;
62
63 *cdebug << "Classic POS module\n";
64
65 pos_lex_name = siod_get_lval("pos_lex_name",NULL__null);
66 if (pos_lex_name == NIL((struct obj *) 0))
67 return utt; // not set so ignore it
68 pos_ngram_name = siod_get_lval("pos_ngram_name","no pos ngram name");
69 pos_p_start_tag = siod_get_lval("pos_p_start_tag","no prev start tag");
70 pos_pp_start_tag = siod_get_lval("pos_pp_start_tag","no prev prev start tag");
71
72 lastlex = lex_select_lex(pos_lex_name);
73
74 if ((pos_ngram = get_ngram(get_c_string(pos_ngram_name))) == 0)
75 {
76 cerr << "POS: no ngram called \"" <<
77 get_c_string(pos_ngram_name) << "\" defined" << endl;
78 festival_error()(errjmp_ok ? longjmp(*est_errjmp,1) : festival_tidy_up(),exit
(-1));
79 }
80
81 p_word = pos_ngram->get_vocab_word(get_c_string(pos_p_start_tag));
82 n_word = pos_ngram->get_vocab_word(get_c_string(pos_pp_start_tag));
83
84 EST_Viterbi_Decoder v(pos_candlist,pos_npath,pos_ngram->num_states());
85
86 v.initialise(u->relation("Word"));
87 v.search();
88 v.result("pos_index");
89
90 lex_select_lex(lastlex);
91
92 EST_Item *w;
93 EST_String pos;
94 LISP l;
95 // Map pos tagset to desired set
96 LISP pos_map = siod_get_lval("pos_map",NULL__null);
97 for (w=u->relation("Word")->first(); w != 0; w = w->next())
98 {
99 // convert pos index into string value
100 pos = pos_ngram->get_vocab_word(w->f("pos_index").Int());
101 w->set("pos",pos);
102 for (l=pos_map; l != NIL((struct obj *) 0); l=cdr(l))
103 if (siod_member_str(pos,car(car(l))) != NIL((struct obj *) 0))
104 {
105 w->set("pos",get_c_string(car(cdr(car(l)))));
106 break;
107 }
108 }
109
110 return utt;
111}
112
113static EST_VTCandidate *pos_candlist(EST_Item *s,EST_Features &f)
114{
115 // Return list of possible pos based on a priori probabilities
116 LISP pd,l;
117 EST_Item *token;
118 EST_VTCandidate *c;
119 EST_VTCandidate *all_c = 0;
120 EST_String actual_pos;
121 (void)f;
122
123 if (((actual_pos = s->S("pos","0")) != "0") ||
124 (((token = parent(s,"Token")) != 0) &&
125 ((actual_pos = token->S("pos","0")) != "0")))
126 {
127 // There is an explicit pos specified, so respect it
128 pd = cons(make_param_float(actual_pos,1.0),NIL((struct obj *) 0));
Value stored to 'pd' is never read
129 c = new EST_VTCandidate;
130 c->name = pos_ngram->get_vocab_word(actual_pos);
131 c->score = 1.0;
132 c->s = s;
133 c->next = 0;
134 return c;
135 }
136
137 LISP e = lex_lookup_word(s->name(),NIL((struct obj *) 0));
138 pd = car(cdr(e));
139
140 if (pd == NIL((struct obj *) 0))
141 {
142 const char *chr = s->name();
143 if (strchr("0123456789",chr[0]) != NULL__null)
144 e = lex_lookup_word("_number_",NIL((struct obj *) 0)); // I *know* there is an entry
145 else
146 e = lex_lookup_word("_OOV_",NIL((struct obj *) 0)); // I *know* there is an entry
147 pd = car(cdr(e));
148 }
149
150 // Build a candidate for each entry in prob distribution
151 for (l=pd; l != NIL((struct obj *) 0); l=cdr(l))
152 {
153 c = new EST_VTCandidate;
154 c->name = pos_ngram->get_vocab_word(get_c_string(car(car(l))));
155 c->score = get_c_float(car(cdr(car(l))));
156 c->s = s;
157 c->next = all_c;
158 all_c = c;
159 }
160
161 return all_c;
162}
163
164static EST_VTPath *pos_npath(EST_VTPath *p,EST_VTCandidate *c,EST_Features &f)
165{
166 // Build a potential new path from previous path and this candidate
167 EST_VTPath *np = new EST_VTPath;
168// static EST_String lscorename("lscore");
169 double prob;
170 double lprob;
171 (void)f;
172
173 np->c = c;
174 np->from = p;
175 int n = c->name.Int();
176 prob = find_np_prob(p,n,&np->state);
177 if (prob == 0)
178 lprob = log(0.00000001);
179 else
180 lprob = log(prob);
181
182// np->set_feature(lscorename,(c->score+lprob));
183 if (p==0)
184 np->score = (c->score+lprob);
185 else
186 np->score = (c->score+lprob) + p->score;
187
188 return np;
189}
190
191static double find_np_prob(EST_VTPath *p,int n,int *state)
192{
193 int oldstate=0;
194
195 if (p==0)
196 { // This could be done once before the search is called
197 int order = pos_ngram->order();
198 EST_IVector window(order);
199 int i;
200
201 window.a_no_check(order-1) = n;
202 window.a_no_check(order-2) = p_word;
203 for (i = order-3; i>=0; i--)
204 window.a_no_check(i) = n_word;
205 oldstate = pos_ngram->find_state_id(window);
206 }
207 else
208 oldstate = p->state;
209 *state = pos_ngram->find_next_state_id(oldstate,n);
210 const EST_DiscreteProbDistribution &pd = pos_ngram->prob_dist(oldstate);
211 if (pd.samples() == 0)
212 return 0;
213 else
214 return (double)pd.probability(n);
215}