CODEWITHSUNDEEP
pythontensorflow
BernardoGO
BernardoGO

Reputation: 1856

Importing TensorFlow graph fails for uninitialized variables

I'm trying to export the multi layer perceptron example as a .pb graph. In order to do it, I have named the input variables and output operation and added the following line:

tf.train.write_graph(sess.graph_def, "./", "graph.pb", False)

To import, I did the following:

with gfile.FastGFile("graph.pb",'rb') as f:

    print("load graph")
    graph_def = tf.GraphDef()
    graph_def.ParseFromString(f.read())
    graph_def = tf.GraphDef()
    graph_def.ParseFromString(f.read())
    _ = tf.import_graph_def(graph_def, name='')
    with tf.Session() as persisted_sess:

        persisted_result = persisted_sess.graph.get_tensor_by_name("output:0")
        avd = persisted_sess.run(persisted_result, feed_dict={"input_x:0": features_t})
        print ("Result:", str(avd))

It does import fine but throws an error for the "run" line.

Traceback (most recent call last):
  File "/usr/lib/python3.5/site-packages/tensorflow/python/client/session.py", line 972, in _do_call
    return fn(*args)
  File "/usr/lib/python3.5/site-packages/tensorflow/python/client/session.py", line 954, in _run_fn
    status, run_metadata)
  File "/usr/lib/python3.5/contextlib.py", line 66, in __exit__
    next(self.gen)
  File "/usr/lib/python3.5/site-packages/tensorflow/python/framework/errors.py", line 463, in raise_exception_on_not_ok_status
    pywrap_tensorflow.TF_GetCode(status))
tensorflow.python.framework.errors.FailedPreconditionError: Attempting to use uninitialized value Variable_3
     [[Node: Variable_3/read = Identity[T=DT_FLOAT, _class=["loc:@Variable_3"], _device="/job:localhost/replica:0/task:0/cpu:0"](Variable_3)]]

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "teste.py", line 56, in <module>
    avd = persisted_sess.run(persisted_result, feed_dict={"input_x:0": features_t})
  File "/usr/lib/python3.5/site-packages/tensorflow/python/client/session.py", line 717, in run
    run_metadata_ptr)
  File "/usr/lib/python3.5/site-packages/tensorflow/python/client/session.py", line 915, in _run
    feed_dict_string, options, run_metadata)
  File "/usr/lib/python3.5/site-packages/tensorflow/python/client/session.py", line 965, in _do_run
    target_list, options, run_metadata)
  File "/usr/lib/python3.5/site-packages/tensorflow/python/client/session.py", line 985, in _do_call
    raise type(e)(node_def, op, message)
tensorflow.python.framework.errors.FailedPreconditionError: Attempting to use uninitialized value Variable_3
     [[Node: Variable_3/read = Identity[T=DT_FLOAT, _class=["loc:@Variable_3"], _device="/job:localhost/replica:0/task:0/cpu:0"](Variable_3)]]

Caused by op 'Variable_3/read', defined at:
  File "teste.py", line 37, in <module>
    _ = tf.import_graph_def(graph_def, name='')
  File "/usr/lib/python3.5/site-packages/tensorflow/python/framework/importer.py", line 285, in import_graph_def
    op_def=op_def)
  File "/usr/lib/python3.5/site-packages/tensorflow/python/framework/ops.py", line 2380, in create_op
    original_op=self._default_original_op, op_def=op_def)
  File "/usr/lib/python3.5/site-packages/tensorflow/python/framework/ops.py", line 1298, in __init__
    self._traceback = _extract_stack()

FailedPreconditionError (see above for traceback): Attempting to use uninitialized value Variable_3
     [[Node: Variable_3/read = Identity[T=DT_FLOAT, _class=["loc:@Variable_3"], _device="/job:localhost/replica:0/task:0/cpu:0"](Variable_3)]]

I have tried to initialize all variables but it does not work.

Upvotes: 0

Views: 924

Answers (1)

Daniel De Freitas
Daniel De Freitas

Reputation: 2653

TensorFlow splits saving the Graph definition and the Variable values in different files (graph and checkpoint respectively).

You want to use the TF Saver.

See this answer for details: https://stackoverflow.com/a/33762168/4120005

Or the documentation here: https://www.tensorflow.org/versions/r0.11/how_tos/variables/index.html#saving-variables

If you really need to restore just from the graphdef file (*.pb), to load it from C++ for instance, you will need to use the freeze_graph.py script from here: https://github.com/tensorflow/tensorflow/blob/master/tensorflow/python/tools/freeze_graph.py

This script takes a graphdef (.pb) and a checkpoint (.ckpt) file as input and outputs a graphdef file which contains the weights in the form of constants (you can read the docs on the script for more details).

Upvotes: 2

Related Questions