Merge pull request #922 from jignparm/jignparm/fix_str_decode

Fix UnicodeDecode error

Author: guschmue

tf2onnx/tf_utils.py

@@ -57,8 +57,11 @@ def tf_to_onnx_tensor(tensor, name=""):
         # assume np_data is string, numpy_helper.from_array accepts ndarray,
         # in which each item is of str while the whole dtype is of object.
         try:
-            np_data = np_data.astype(np.str).astype(np.object)
-        except: # pylint: disable=bare-except
+            if len(np_data.shape) > 0:
+                np_data = np_data.astype(np.str).astype(np.object)
+            else:
+                np_data = np.array(str(np_data)).astype(np.object)
+        except:  # pylint: disable=bare-except
             raise RuntimeError("Not support type: {}".format(type(np_data.flat[0])))
     return numpy_helper.from_array(np_data, name=name)