REFACTO: in split setting, remove checking NaNs and irrelevant aggregation to avoid triggering unwanted warnings (#586)

* REFACTO: in split setting, remove checking NaNs and irrelevant aggregation to avoid triggering unwanted warnings

Author: Valentin-Laurent

mapie/estimator/regressor.py

@@ -402,9 +402,12 @@ def predict_calib(
                         predictions[i], dtype=float
                     )
                     self.k_[ind, i] = 1
-                check_nan_in_aposteriori_prediction(pred_matrix)
 
-                y_pred = aggregate_all(self.agg_function, pred_matrix)
+                if self.use_split_method_:
+                    y_pred = pred_matrix.flatten()
+                else:
+                    check_nan_in_aposteriori_prediction(pred_matrix)
+                    y_pred = aggregate_all(self.agg_function, pred_matrix)
 
         return y_pred
 

mapie/tests/test_regression.py

@@ -701,7 +701,7 @@ def test_not_enough_resamplings() -> None:
     """
     with pytest.warns(UserWarning, match=r"WARNING: at least one point of*"):
         mapie_reg = MapieRegressor(
-            cv=Subsample(n_resamplings=1), agg_function="mean"
+            cv=Subsample(n_resamplings=2, random_state=0), agg_function="mean"
         )
         mapie_reg.fit(X, y)
 

mapie/tests/test_time_series_regression.py

@@ -318,7 +318,8 @@ def test_not_enough_resamplings() -> None:
         match=r"WARNING: at least one point of*"
     ):
         mapie_ts_reg = MapieTimeSeriesRegressor(
-            cv=BlockBootstrap(n_resamplings=1, n_blocks=1), agg_function="mean"
+            cv=BlockBootstrap(n_resamplings=2, n_blocks=1, random_state=0),
+            agg_function="mean"
         )
         mapie_ts_reg.fit(X, y)