ENH Simplify error message of get_scorer (#11738)

qinhanmin2014 · rth · commit 825cf09a1e40 · 2018-08-06T12:30:35.000+03:00
diff --git a/doc/modules/model_evaluation.rst b/doc/modules/model_evaluation.rst
@@ -105,7 +105,7 @@ Usage examples:
     >>> model = svm.SVC()
     >>> cross_val_score(model, X, y, cv=5, scoring='wrong_choice')
     Traceback (most recent call last):
-    ValueError: 'wrong_choice' is not a valid scoring value. Valid options are ['accuracy', 'adjusted_mutual_info_score', 'adjusted_rand_score', 'average_precision', 'balanced_accuracy', 'brier_score_loss', 'completeness_score', 'explained_variance', 'f1', 'f1_macro', 'f1_micro', 'f1_samples', 'f1_weighted', 'fowlkes_mallows_score', 'homogeneity_score', 'mutual_info_score', 'neg_log_loss', 'neg_mean_absolute_error', 'neg_mean_squared_error', 'neg_mean_squared_log_error', 'neg_median_absolute_error', 'normalized_mutual_info_score', 'precision', 'precision_macro', 'precision_micro', 'precision_samples', 'precision_weighted', 'r2', 'recall', 'recall_macro', 'recall_micro', 'recall_samples', 'recall_weighted', 'roc_auc', 'v_measure_score']
+    ValueError: 'wrong_choice' is not a valid scoring value. Use sorted(sklearn.metrics.SCORERS.keys()) to get valid options.
 
 .. note::
 
diff --git a/sklearn/metrics/scorer.py b/sklearn/metrics/scorer.py
@@ -216,8 +216,8 @@ def get_scorer(scoring):
             scorer = SCORERS[scoring]
         except KeyError:
             raise ValueError('%r is not a valid scoring value. '
-                             'Valid options are %s'
-                             % (scoring, sorted(SCORERS.keys())))
+                             'Use sorted(sklearn.metrics.SCORERS.keys()) '
+                             'to get valid options.' % (scoring))
     else:
         scorer = scoring
     return scorer
