Merge pull request #3375 from matkoniecz/patch-1

[nominatim.git] / nominatim / api / search / geocoder.py

diff --git a/nominatim/api/search/geocoder.py b/nominatim/api/search/geocoder.py
index 6b58c9457c16598ea8c735f8bcdb5d55a820febf..775606aab755d6f68180e696828115c285a99f11 100644 (file)
--- a/nominatim/api/search/geocoder.py
+++ b/nominatim/api/search/geocoder.py
@@ -95,7 +95,7 @@ class ForwardGeocoder:
                     prevresult.accuracy = min(prevresult.accuracy, result.accuracy)
                 else:
                     results[rhash] = result
                     prevresult.accuracy = min(prevresult.accuracy, result.accuracy)
                 else:
                     results[rhash] = result

-                min_ranking = min(min_ranking, result.accuracy * 1.2)
+                min_ranking = min(min_ranking, result.accuracy * 1.2, 2.0)

             log().result_dump('Results', ((r.accuracy, r) for r in lookup_results))
             prev_penalty = search.penalty
             if dt.datetime.now() >= end_time:
             log().result_dump('Results', ((r.accuracy, r) for r in lookup_results))
             prev_penalty = search.penalty
             if dt.datetime.now() >= end_time:


@@ -104,19 +104,27 @@ class ForwardGeocoder:
         return SearchResults(results.values())
 
 
         return SearchResults(results.values())
 
 

+    def pre_filter_results(self, results: SearchResults) -> SearchResults:
+        """ Remove results that are significantly worse than the
+            best match.
+        """
+        if results:
+            max_ranking = min(r.ranking for r in results) + 0.5
+            results = SearchResults(r for r in results if r.ranking < max_ranking)
+
+        return results
+
+

     def sort_and_cut_results(self, results: SearchResults) -> SearchResults:
         """ Remove badly matching results, sort by ranking and
             limit to the configured number of results.
         """
         if results:
     def sort_and_cut_results(self, results: SearchResults) -> SearchResults:
         """ Remove badly matching results, sort by ranking and
             limit to the configured number of results.
         """
         if results:

-            min_ranking = min(r.ranking for r in results)
-            results = SearchResults(r for r in results if r.ranking < min_ranking + 0.5)

             results.sort(key=lambda r: r.ranking)
             results.sort(key=lambda r: r.ranking)

-
-        if results:

             min_rank = results[0].rank_search
             min_rank = results[0].rank_search

+            min_ranking = results[0].ranking

             results = SearchResults(r for r in results
             results = SearchResults(r for r in results

-                                    if r.ranking + 0.05 * (r.rank_search - min_rank)
+                                    if r.ranking + 0.03 * (r.rank_search - min_rank)

                                        < min_ranking + 0.5)
 
             results = SearchResults(results[:self.limit])
                                        < min_ranking + 0.5)
 
             results = SearchResults(results[:self.limit])


@@ -141,7 +149,8 @@ class ForwardGeocoder:
                or (result.importance is not None and result.importance < 0):
                 continue
             distance = 0.0
                or (result.importance is not None and result.importance < 0):
                 continue
             distance = 0.0

-            norm = self.query_analyzer.normalize_text(result.display_name)
+            norm = self.query_analyzer.normalize_text(' '.join((result.display_name,
+                                                                result.country_code or '')))

             words = set((w for w in norm.split(' ') if w))
             if not words:
                 continue
             words = set((w for w in norm.split(' ') if w))
             if not words:
                 continue


@@ -173,6 +182,7 @@ class ForwardGeocoder:
             if query:
                 searches = [wrap_near_search(categories, s) for s in searches[:50]]
                 results = await self.execute_searches(query, searches)
             if query:
                 searches = [wrap_near_search(categories, s) for s in searches[:50]]
                 results = await self.execute_searches(query, searches)

+                results = self.pre_filter_results(results)

                 await add_result_details(self.conn, results, self.params)
                 log().result_dump('Preliminary Results', ((r.accuracy, r) for r in results))
                 results = self.sort_and_cut_results(results)
                 await add_result_details(self.conn, results, self.params)
                 log().result_dump('Preliminary Results', ((r.accuracy, r) for r in results))
                 results = self.sort_and_cut_results(results)


@@ -202,6 +212,7 @@ class ForwardGeocoder:
         if searches:
             # Execute SQL until an appropriate result is found.
             results = await self.execute_searches(query, searches[:50])
         if searches:
             # Execute SQL until an appropriate result is found.
             results = await self.execute_searches(query, searches[:50])

+            results = self.pre_filter_results(results)

             await add_result_details(self.conn, results, self.params)
             log().result_dump('Preliminary Results', ((r.accuracy, r) for r in results))
             self.rerank_by_query(query, results)
             await add_result_details(self.conn, results, self.params)
             log().result_dump('Preliminary Results', ((r.accuracy, r) for r in results))
             self.rerank_by_query(query, results)