ENH improve error message when y_true does not provide all known classes (#21757)

glemaitre · jjerphan · web-flow · commit 64782c07c6ad · 2022-01-28T15:05:27.000+01:00
Co-authored-by: Julien Jerphanion &lt;git@jjerphan.xyz&gt;
diff --git a/sklearn/metrics/_ranking.py b/sklearn/metrics/_ranking.py
@@ -1722,6 +1722,8 @@ def top_k_accuracy_score(
             raise ValueError(
                 f"Number of classes in 'y_true' ({n_classes}) not equal "
                 f"to the number of classes in 'y_score' ({y_score_n_classes})."
+                "You can provide a list of all known classes by assigning it "
+                "to the `labels` parameter."
             )
     else:
         labels = column_or_1d(labels)

Original file line number	Diff line number	Diff line change
`@@ -1722,6 +1722,8 @@ def top_k_accuracy_score(`
`1722`	`1722`	`raise ValueError(`
`1723`	`1723`	`f"Number of classes in 'y_true' ({n_classes}) not equal "`
`1724`	`1724`	`f"to the number of classes in 'y_score' ({y_score_n_classes})."`
	`1725`	`+ "You can provide a list of all known classes by assigning it "`
	`1726`	+ "to the `labels` parameter."
`1725`	`1727`	`)`
`1726`	`1728`	`else:`
`1727`	`1729`	`labels = column_or_1d(labels)`