def test_get_normalized_probabilities(self):
probability_list = [0.2, 0.3, 0.2]
ans = [0.28571428571428575, 0.4285714285714286, 0.28571428571428575]
actual_list = utils.get_normalized_probabilities(probability_list)
for i in xrange(len(actual_list)):
self.assertAlmostEqual(actual_list[i], ans[i])
self.assertAlmostEqual(sum(actual_list), 1.0)
def generate_suggestions_and_posteriors(self, query,
get_posterior_fn = None):
"""Return (suggestion, posterior) pairs for query.
Get a list of candidate suggestions and calculate posteriors
for each of them.
Arguments:
- `query`: Suggestion object.
"""
if get_posterior_fn == None:
get_posterior_fn = self.get_posterior_fn
# all_queries = [query] + utils.get_corrected_split_queries(query, self.lexicon) \
# + utils.get_corrected_run_on_queries(query, self.lexicon)
all_queries = [query] + utils.get_corrected_split_queries(query, self.lexicon)
# + utils.get_corrected_run_on_queries(query, self.lexicon)
# print 'all_queries'
# pprint(all_queries)
# List of list of (query, suggestion, likelihood) for each query
all_suggestions = [[(query, suggestion)
for suggestion in self.generate_candidate_suggestions(
map(self.generate_candidate_terms, query),
query.suggestion_type)]
for query in all_queries]
# Flatten the list of list of suggestions
all_suggestions = list(itertools.chain(*all_suggestions))
# print 'all_suggestions after flattening'
# pprint(all_suggestions)
all_suggestions.sort(key = lambda query_sugg_tuple:
phrase.get_likelihood(*query_sugg_tuple),
reverse = True)
# print 'suggestions and likelihood'
# pprint([(query, suggestion, phrase.get_likelihood(query, suggestion))
# for query, suggestion in all_suggestions])
# Remove duplicates (if any)
all_suggestions = [key for key, _ in itertools.groupby(all_suggestions)]
# print 'all_suggestions after removing duplicates'
# pprint(all_suggestions)
# Take only the top few suggestions
all_suggestions = all_suggestions[:self.MAX_NUM_SUGGESTIONS]
# print 'len(all_suggestions)'
# pprint(len(all_suggestions))
# print 'all_suggestions after taking off the top'
# pprint(all_suggestions)
all_posteriors = [get_posterior_fn(suggestion, query)
for query, suggestion in all_suggestions]
all_suggestions = list(zip(*all_suggestions)[1])
# TODO
# original_query = query
# original_query_posterior = get_posterior_fn(query, query)
# print 'original_query'
# pprint(original_query, original_query_posterior)
# if original_query_posterior > self.ORIGINAL_POSTERIOR_THRESHOLD:
# all_suggestions += [original_query]
# all_posteriors += [original_query_posterior]
normalized_posteriors = utils.get_normalized_probabilities(all_posteriors)
suggestion_posterior_list = list(zip(all_suggestions, normalized_posteriors))
suggestion_posterior_list.sort(key = lambda pair: pair[1], reverse = True)
return suggestion_posterior_list
