Add top_n

haystack/reader/farm.py

@@ -471,6 +471,7 @@ def eval(
             "EM": eval_results[0]["EM"],
             "f1": eval_results[0]["f1"],
             "top_n_accuracy": eval_results[0]["top_n_accuracy"],
+            "top_n": self.inferencer.model.prediction_heads[0].n_best,
             "reader_time": reader_time,
             "seconds_per_query": reader_time / n_queries
         }

test/benchmarks/reader.py

@@ -37,6 +37,7 @@ def benchmark():
                 results = {'EM': 0.,
                            'f1': 0.,
                            'top_n_accuracy': 0.,
+                           'top_n': 0,
                            'reader_time': 0.,
                            "passages_per_second": 0.,
                            "seconds_per_query": 0.,