Tweak a helper function to always return a 1-D array.

Author: njhenry

src/openpois/models/model_fitter.py

@@ -166,7 +166,7 @@ def _to_table(self, x):
         """
         Helper function to convert a tensor to a numpy array.
         """
-        return x.data.cpu().numpy()
+        return x.data.cpu().numpy().reshape(-1)
 
     def get_parameter_table(
         self,