void sentence_delete(Sentence sent) {
/*free_andlists(sent); */
free_sentence_disjuncts(sent);
free_sentence_expressions(sent);
string_set_delete(sent->string_set);
free_parse_set(sent);
free_post_processing(sent);
post_process_close_sentence(sent->dict->postprocessor);
free_lookup_list();
free_deletable(sent);
free_effective_dist(sent);
xfree(sent->is_conjunction, sizeof(char)*sent->length);
xfree((char *) sent, sizeof(struct Sentence_s));
}
void build_effective_dist(Sentence sent, int has_conjunction) {
/*
The "effective distance" between two words is the actual distance minus
the largest deletable region strictly between the two words. If the
effective distance between two words is greater than a connector's max
link length, then that connector cannot be satisfied by linking these
two words.
[Note: The effective distance is not monotically increasing as you move
away from a word.]
This function creates effective_dist[][]. It assumes that deleteble[][]
has already been computed.
Dynamic programming is used to compute this. The order used is smallest
region to largest.
Just as deletable[i][j] is constructed for j=N_words (which is one
off the end of the sentence) we do that for effective_dist[][].
*/
int i, j, diff;
free_effective_dist(sent);
sent->effective_dist = (char **) xalloc((sent->length)*sizeof(char *));
for (i=0; i<sent->length; i++) {
sent->effective_dist[i] = (char *) xalloc(sent->length+1);
}
for (i=0; i<sent->length; i++) {
/* Fill in the silly part */
for (j=0; j<=i; j++) {
sent->effective_dist[i][j] = j-i;
}
}
/* what is the rationale for ignoring the effective_dist
if null links are allowed? */
if (null_links) {
for (i=0; i<sent->length; i++) {
for (j=0; j<=sent->length; j++) {
sent->effective_dist[i][j] = j-i;
}
}
}
else {
for (diff = 1; diff < sent->length; diff++) {
for (i=0; i+diff <= sent->length; i++) {
j = i+diff;
if (sent->deletable[i][j]) { /* note that deletable[x][x+1] is TRUE */
sent->effective_dist[i][j] = 1;
} else {
sent->effective_dist[i][j] = 1 + MIN(sent->effective_dist[i][j-1],sent->effective_dist[i+1][j]);
}
}
}
/* now when you link to a conjunction, your effective length is 1 */
for (i=0; i<sent->length; i++) {
for (j=i+1; j<sent->length; j++) {
if (sent->is_conjunction[i] ||
sent->is_conjunction[j]) sent->effective_dist[i][j] = 1;
}
}
}
/* sent->effective_dist[i][i] should be 0 */
/*
for (j=0; j<=sent->length; j++) {
printf("%4d", j);
}
printf("\n");
for (i=0; i<sent->length; i++) {
for (j=0; j<=sent->length; j++) {
printf("%4d", sent->effective_dist[i][j]);
}
printf("\n");
}
*/
}
