Upload madelon.py

madelon.py

@@ -70,6 +70,6 @@ class Madelon(datasets.GeneratorBasedBuilder):
                 yield row_id, data_row
 
     def preprocess(self, data: pandas.DataFrame, config: str = DEFAULT_CONFIG) -> pandas.DataFrame:
-        data["500"].apply(lambda x: max(0, x))
+        data["500"] = data["500"].apply(lambda x: max(0, x)).astype(int)
 
         return data