tf.contrib.training.FeedingQueueRunner

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A queue runner that allows the feeding of values such as numpy arrays.

Inherits From: QueueRunner

tf.contrib.training.FeedingQueueRunner(
    queue=None, enqueue_ops=None, close_op=None, cancel_op=None, feed_fns=None,
    queue_closed_exception_types=None
)

queue A Queue.
enqueue_ops List of enqueue ops to run in threads later.
close_op Op to close the queue. Pending enqueue ops are preserved.
cancel_op Op to close the queue and cancel pending enqueue ops.
feed_fns a list of functions that return a dictionary mapping fed Tensors to values. Must be the same length as enqueue_ops.
queue_closed_exception_types Optional tuple of Exception types that indicate that the queue has been closed when raised during an enqueue operation. Defaults to (tf.errors.OutOfRangeError, tf.errors.CancelledError).

ValueError feed_fns is not None and has different length than enqueue_ops.

cancel_op

close_op

enqueue_ops

exceptions_raised Exceptions raised but not handled by the QueueRunner threads.

Exceptions raised in queue runner threads are handled in one of two ways depending on whether or not a Coordinator was passed to create_threads():

  • With a Coordinator, exceptions are reported to the coordinator and forgotten by the QueueRunner.
  • Without a Coordinator, exceptions are captured by the QueueRunner and made available in this exceptions_raised property.
name The string name of the underlying Queue.
queue

queue_closed_exception_types

Methods

create_threads

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create_threads(
    sess, coord=None, daemon=False, start=False
)

Create threads to run the enqueue ops for the given session.

This method requires a session in which the graph was launched. It creates a list of threads, optionally starting them. There is one thread for each op passed in enqueue_ops.

The coord argument is an optional coordinator, that the threads will use to terminate together and report exceptions. If a coordinator is given, this method starts an additional thread to close the queue when the coordinator requests a stop.

If previously created threads for the given session are still running, no new threads will be created.

Args
sess A Session.
coord Optional Coordinator object for reporting errors and checking stop conditions.
daemon Boolean. If True make the threads daemon threads.
start Boolean. If True starts the threads. If False the caller must call the start() method of the returned threads.

Returns
A list of threads.

from_proto

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@staticmethod
from_proto(
    queue_runner_def, import_scope=None
)

Returns a QueueRunner object created from queue_runner_def.

to_proto

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to_proto()

Converts this QueueRunner to a QueueRunnerDef protocol buffer.

Args
export_scope Optional string. Name scope to remove.

Returns
A QueueRunnerDef protocol buffer, or None if the Variable is not in the specified name scope.