[BUG] Remove squaring distances in KNN regression (#1697)

* remove unnecessary ExponentTransform import

* remove squaring

Author: TonyBagnall

aeon/regression/distance_based/_time_series_neighbors.py

@@ -172,7 +172,6 @@ def _kneighbors(self, X):
 
         if self.weights == "distance":
             ws = distances[closest_idx]
-            ws = ws**2
 
             # Using epsilon ~= 0 to avoid division by zero
             ws = 1 / (ws + np.finfo(float).eps)

aeon/regression/distance_based/tests/test_time_series_neighbors.py

@@ -20,6 +20,6 @@ def test_knn_neighbors():
     model.fit(X_train, y_train)
 
     y_pred = model.predict(X_test)
-    y_pred_expected = np.array([-216.06541863, -4.54133078, -324.7624233])
+    y_pred_expected = np.array([-144.410377008, -25.55876587, -229.9764678])
 
-    assert np.abs(y_pred - y_pred_expected).max() < 1e-6
+    assert np.abs(y_pred - y_pred_expected).max() < 1e-4