Merge branch 'lukas_issue074_bug_ols-force-add-constant' into 'develop'

apply bug fix to dev too

See merge request toar/machinelearningtools!67

src/model_modules/linear_model.py

@@ -31,7 +31,7 @@ class OrdinaryLeastSquaredModel:
         self.y = data_y
 
     def predict(self, data):
-        data = sm.add_constant(self.reshape_xarray_to_numpy(data))
+        data = sm.add_constant(self.reshape_xarray_to_numpy(data), has_constant="add")
         return np.atleast_2d(self.model.predict(data))
 
     @staticmethod

test/test_model_modules/test_linear_model.py

+
+from src.model_modules.linear_model import OrdinaryLeastSquaredModel
+
+
+class TestOrdinaryLeastSquareModel:
+
+    def test_constant_input_variable(self):
+        pass