使张量流模型中的一个输入保持不变答案

【问题标题】：Making one input in a tensorflow model constant使张量流模型中的一个输入保持不变
【发布时间】：2020-06-22 23:29:06
【问题描述】：

我有以下问题：我使用 deepchem 创建了一个模型，它是一个包装好的 keras 模型，对其进行了训练并重新加载了它。我可以毫无问题地预测使用这个模型。现在我想复制这个模型，它少了一个输入，因为一个输入在我的使用场景中始终保持不变，并且总是传递它会导致我无法编辑的函数中出现错误。

data = np.array(data.data, dtype=float32)
    with tf.Graph().as_default() as temp_graph:
        tf.import_graph_def(self.model.session.graph.as_graph_def(),
                            input_map={self.model._input_placeholders[1].name: 
                                       tf.constant(np.array([0], dtype=float32)),})
    #self.model.session.graph = temp_graph
    #for deep explainer: replace all switched dropouts with dropouts 
    #get input tensor for this graph 
    tensors = tf.contrib.graph_editor.get_tensors(temp_graph)
    for t in tensors:
        if "input_1" in t.name:
            input_tensor = t
            break
    #reshape output --> only singletask!
    output = tf.reshape(tensors[-1], [-1, 1])
    model = (input_tensor, output)
    sess = tf.Session(graph=temp_graph)
    feed_dict = dict(zip([input_tensor], [data]))
    print(sess.run(output, feed_dict))

在这段代码片段中，我能够加载我的模型的图形并将一个常量传递给它的输入。现在显然我不能在同一个会话中运行这个新模型，因为那个会话包含旧模型。无法更改使用 feed dict 运行模型的方式，因为它在真实场景中位于另一个包中。我收到以下错误消息：

Error while reading resource variable dense_2/bias from Container: localhost. This could mean that the variable was uninitialized. Not found: Container localhost does not exist.

完整的跟踪是：

Traceback (most recent call last):
  File "/EXT/Tobha/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1356, in _do_call
    return fn(*args)
  File "/EXT/Tobha/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1341, in _run_fn
    options, feed_dict, fetch_list, target_list, run_metadata)
  File "/EXT/Tobha/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1429, in _call_tf_sessionrun
    run_metadata)
tensorflow.python.framework.errors_impl.FailedPreconditionError: Error while reading resource variable dense_2/bias from Container: localhost. This could mean that the variable was uninitialized. Not found: Container localhost does not exist. (Could not find resource: localhost/dense_2/bias)
     [[{{node import/model/dense_2/BiasAdd/ReadVariableOp}}]]

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/EXT/Tobha/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/Models.py", line 490, in <module>
    main()
  File "/EXT/Tobha/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/Models.py", line 478, in main
    evaluate()
  File "/EXT/Tobha/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/Models.py", line 445, in evaluate
    reader.explain()
  File "/EXT/Tobha/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/DataHandling.py", line 1534, in explain
    self.explain()
  File "/EXT/Tobha/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/DataHandling.py", line 1519, in explain
    self._explain_Gradient_SHAP(self.df)
  File "/EXT/Tobha/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/DataHandling.py", line 2047, in _explain_Gradient_SHAP
    print(sess.run(output, feed_dict))
  File "/EXT/Tobha/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 950, in run
    run_metadata_ptr)
  File "/EXT/Tobha/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1173, in _run
    feed_dict_tensor, options, run_metadata)
  File "/EXT/Tobha/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1350, in _do_run
    run_metadata)
  File "/EXT/Tobha/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1370, in _do_call
    raise type(e)(node_def, op, message)
tensorflow.python.framework.errors_impl.FailedPreconditionError: Error while reading resource variable dense_2/bias from Container: localhost. This could mean that the variable was uninitialized. Not found: Container localhost does not exist. (Could not find resource: localhost/dense_2/bias)
     [[node import/model/dense_2/BiasAdd/ReadVariableOp (defined at /eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/DataHandling.py:2033) ]]

Original stack trace for 'import/model/dense_2/BiasAdd/ReadVariableOp':
  File "/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/Models.py", line 490, in <module>
    main()
  File "/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/Models.py", line 478, in main
    evaluate()
  File "/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/Models.py", line 445, in evaluate
    reader.explain()
  File "/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/DataHandling.py", line 1534, in explain
    self.explain()
  File "/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/DataHandling.py", line 1519, in explain
    self._explain_Gradient_SHAP(self.df)
  File "/eclipse-workspace/Bachelorarbeit/toolbox_dc_2_3_0/python_source/DataHandling.py", line 2033, in _explain_Gradient_SHAP
    tf.constant(np.array([0], dtype=float32)),})
  File "/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/util/deprecation.py", line 507, in new_func
    return func(*args, **kwargs)
  File "/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/framework/importer.py", line 443, in import_graph_def
    _ProcessNewOps(graph)
  File "/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/framework/importer.py", line 236, in _ProcessNewOps
    for new_op in graph._add_new_tf_operations(compute_devices=False):  # pylint: disable=protected-access
  File "/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 3751, in _add_new_tf_operations
    for c_op in c_api_util.new_tf_operations(self)
  File "/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 3751, in <listcomp>
    for c_op in c_api_util.new_tf_operations(self)
  File "/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 3641, in _create_op_from_tf_operation
    ret = Operation(c_op, self)
  File "/.conda/envs/test_BA_Tobias_std_deepchem-2-3-0_py36_20200114/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 2005, in __init__
    self._traceback = tf_stack.extract_stack()

我正在使用 tensorflow 1.14 和 Python 3.6（这也无法更改）

所以我的问题可以通过 2 种不同的方式解决：或者我可以使用旧会话中的信息运行第二个图表，或者我可以告诉旧会话使用一个常量输入。

提前感谢您的帮助！

最好的问候托比亚斯

编辑：我最终通过包装我试图使用的类并覆盖一些方法来解决这个问题。我认为另一个想法可能是用 keras 常量替换一个 Keras 输入。

【问题讨论】：

标签： python tensorflow keras

【解决方案1】：

这个错误有点棘手。以下是我想到的一些建议：

DeepChem HEAD 现在在 TensorFlow 2.X 上运行。如果您的问题在 Eager 模式下更容易处理，那可能是一种选择。当然，HEAD 不稳定，可能还会出现其他问题。
DeepChem 模型位于仅由 Keras 层构成的引擎盖下方。如果您可以从模型的组成层制作 Keras 模型，那么您可以避免使用 DeepChem 包装器并直接在 Keras 中解决问题。

添加更多关于您尝试使用的 DeepChem 模型以及您在其中看到错误的下游函数的信息也可能会有所帮助。

【讨论】：