Python dataset_ops.make_initializable_iterator函数代码示例

  def testMultipleDatasetWithPrefixes(self, dataset_transformation):
    aggregator = stats_aggregator.StatsAggregator()
    dataset = dataset_ops.Dataset.range(100).apply(
        stats_ops.latency_stats("record_latency"))
    dataset = dataset_transformation(dataset, aggregator, prefix="dataset1")
    dataset2 = dataset_ops.Dataset.range(100).apply(
        stats_ops.latency_stats("record_latency"))
    dataset2 = dataset_transformation(dataset2, aggregator, prefix="dataset2")
    iterator_0 = dataset_ops.make_initializable_iterator(dataset)
    iterator_1 = dataset_ops.make_initializable_iterator(dataset2)
    next_element = iterator_0.get_next() + iterator_1.get_next()
    summary_t = aggregator.get_summary()

    with self.test_session() as sess:
      self.evaluate([iterator_0.initializer, iterator_1.initializer])
      for i in range(100):
        self.assertEqual(i * 2, self.evaluate(next_element))
        self._assertSummaryHasCount(
            self.evaluate(summary_t), "dataset1_record_latency", float(i + 1))
        self._assertSummaryHasCount(
            self.evaluate(summary_t), "dataset2_record_latency", float(i + 1))
      with self.assertRaises(errors.OutOfRangeError):
        self.evaluate(next_element)
      self._assertSummaryHasCount(
          self.evaluate(summary_t), "dataset1_record_latency", 100.0)
      self._assertSummaryHasCount(
          self.evaluate(summary_t), "dataset2_record_latency", 100.0)

  def testPrefetchToDeviceWithReInit(self):
    host_dataset = dataset_ops.Dataset.range(10)
    device_dataset = host_dataset.apply(
        prefetching_ops.prefetch_to_device("/cpu:1"))

    with ops.device("/cpu:1"):
      iterator = dataset_ops.make_initializable_iterator(device_dataset)
      next_element = iterator.get_next()

    self.assertTrue(dataset_ops.get_structure(host_dataset).is_compatible_with(
        dataset_ops.get_structure(device_dataset)))
    self.assertTrue(dataset_ops.get_structure(host_dataset).is_compatible_with(
        dataset_ops.get_structure(iterator)))

    self.assertEqual(dtypes.int64, next_element.dtype)
    self.assertEqual([], next_element.shape)

    worker_config = config_pb2.ConfigProto(device_count={"CPU": 2})
    with self.test_session(config=worker_config):
      self.evaluate(iterator.initializer)
      for i in range(5):
        self.assertEqual(i, self.evaluate(next_element))
      self.evaluate(iterator.initializer)
      for i in range(10):
        self.assertEqual(i, self.evaluate(next_element))
      with self.assertRaises(errors.OutOfRangeError):
        self.evaluate(next_element)

  def test_sequence_file_dataset(self):
    """Test case for SequenceFileDataset.

    The file is generated with `org.apache.hadoop.io.Text` for key/value.
    There are 25 records in the file with the format of:
    key = XXX
    value = VALUEXXX
    where XXX is replaced as the line number (starts with 001).
    """
    filename = os.path.join(resource_loader.get_data_files_path(),
                            "testdata", "string.seq")

    filenames = constant_op.constant([filename], dtypes.string)
    num_repeats = 2

    dataset = hadoop_dataset_ops.SequenceFileDataset(filenames).repeat(
        num_repeats)
    iterator = dataset_ops.make_initializable_iterator(dataset)
    init_op = iterator.initializer
    get_next = iterator.get_next()

    with self.cached_session() as sess:
      sess.run(init_op)
      for _ in range(num_repeats):  # Dataset is repeated.
        for i in range(25):  # 25 records.
          v0 = b"%03d" % (i + 1)
          v1 = b"VALUE%03d" % (i + 1)
          self.assertEqual((v0, v1), sess.run(get_next))
      with self.assertRaises(errors.OutOfRangeError):
        sess.run(get_next)

  def testSkipEagerSplitPipelineFailsWithPlacementError(self):
    with session.Session(
        target="",
        config=config_pb2.ConfigProto(device_count={"CPU": 2})) as sess:

      dataset = dataset_ops.Dataset.from_tensors(0)

      # Define a pipeline that attempts to use variables on two
      # different devices.
      #
      # Initialize the variables before creating to iterator, to avoid the
      # placement algorithm overriding the DT_RESOURCE colocation constraints.
      with ops.device("/cpu:0"):
        var_0 = resource_variable_ops.ResourceVariable(initial_value=0)
        dataset = dataset.map(lambda x: x + var_0.read_value())
      sess.run(var_0.initializer)

      with ops.device("/cpu:1"):
        var_1 = resource_variable_ops.ResourceVariable(initial_value=0)
        dataset = dataset.map(lambda x: x + var_1.read_value())
      sess.run(var_1.initializer)

      iterator = dataset_ops.make_initializable_iterator(dataset)
      sess.run(iterator.initializer)

      with self.assertRaisesRegexp(
          errors.FailedPreconditionError,
          "Error while reading resource variable Variable"):
        sess.run(iterator.get_next())

  def getNext(self, dataset, requires_initialization=False):
    """Returns a callable that returns the next element of the dataset.

    Example use:
    ```python
    # In both graph and eager modes
    dataset = ...
    get_next = self.getNext(dataset)
    result = self.evaluate(get_next())
    ```

    Args:
      dataset: A dataset whose elements will be returned.
      requires_initialization: Indicates that when the test is executed in graph
        mode, it should use an initializable iterator to iterate through the
        dataset (e.g. when it contains stateful nodes). Defaults to False.
    Returns:
      A callable that returns the next element of `dataset`.
    """
    if context.executing_eagerly():
      iterator = dataset.__iter__()
      return iterator._next_internal  # pylint: disable=protected-access
    else:
      if requires_initialization:
        iterator = dataset_ops.make_initializable_iterator(dataset)
        self.evaluate(iterator.initializer)
      else:
        iterator = dataset_ops.make_one_shot_iterator(dataset)
      get_next = iterator.get_next()
      return lambda: get_next

  def test_assert_element_shape(self):

    def create_dataset(_):
      return (array_ops.ones(2, dtype=dtypes.float32),
              array_ops.zeros((3, 4), dtype=dtypes.int32))

    dataset = dataset_ops.Dataset.range(5).map(create_dataset)
    expected_shapes = (tensor_shape.TensorShape(2),
                       tensor_shape.TensorShape((3, 4)))
    self.assertEqual(expected_shapes,
                     dataset_ops.get_legacy_output_shapes(dataset))

    result = dataset.apply(batching.assert_element_shape(expected_shapes))
    self.assertEqual(expected_shapes,
                     dataset_ops.get_legacy_output_shapes(result))

    iterator = dataset_ops.make_initializable_iterator(result)
    init_op = iterator.initializer
    get_next = iterator.get_next()
    with self.cached_session() as sess:
      sess.run(init_op)
      for _ in range(5):
        sess.run(get_next)
      with self.assertRaises(errors.OutOfRangeError):
        sess.run(get_next)

  def testPrefetchBufferUtilization(self, dataset_transformation):
    aggregator = stats_aggregator.StatsAggregator()
    dataset = dataset_ops.Dataset.range(100).map(
        lambda x: array_ops.tile([x], ops.convert_to_tensor([x]))).prefetch(-1)
    dataset = dataset_transformation(dataset, aggregator)
    iterator = dataset_ops.make_initializable_iterator(dataset)
    next_element = iterator.get_next()
    summary_t = aggregator.get_summary()

    with self.cached_session() as sess:
      self.evaluate(iterator.initializer)
      for i in range(100):
        self.assertAllEqual(
            np.array([i] * i, dtype=np.int64), self.evaluate(next_element))
        summary_str = self.evaluate(summary_t)
        self._assertSummaryHasCount(summary_str, "Prefetch::buffer_utilization",
                                    float(i + 1))
        self._assertSummaryContains(summary_str, "Prefetch::buffer_capacity")
        self._assertSummaryContains(summary_str, "Prefetch::buffer_size")
        self._assertSummaryHasRange(summary_str, "Prefetch::buffer_utilization",
                                    0, 1)
      with self.assertRaises(errors.OutOfRangeError):
        self.evaluate(next_element)
      summary_str = self.evaluate(summary_t)
      self._assertSummaryHasCount(summary_str, "Prefetch::buffer_utilization",
                                  100)

  def _testNumThreadsHelper(self, num_threads, override_threadpool_fn):

    def get_thread_id(_):
      # Python creates a dummy thread object to represent the current
      # thread when called from an "alien" thread (such as a
      # `PrivateThreadPool` thread in this case). It does not include
      # the TensorFlow-given display name, but it has a unique
      # identifier that maps one-to-one with the underlying OS thread.
      return np.array(threading.current_thread().ident).astype(np.int64)

    dataset = (
        dataset_ops.Dataset.range(1000).map(
            lambda x: script_ops.py_func(get_thread_id, [x], dtypes.int64),
            num_parallel_calls=32).apply(unique.unique()))
    dataset = override_threadpool_fn(dataset)
    iterator = dataset_ops.make_initializable_iterator(dataset)
    next_element = iterator.get_next()

    self.evaluate(iterator.initializer)
    thread_ids = []
    try:
      while True:
        thread_ids.append(self.evaluate(next_element))
    except errors.OutOfRangeError:
      pass
    self.assertLen(thread_ids, len(set(thread_ids)))
    self.assertNotEmpty(thread_ids)
    if num_threads:
      # NOTE(mrry): We don't control the thread pool scheduling, and
      # so cannot guarantee that all of the threads in the pool will
      # perform work.
      self.assertLessEqual(len(thread_ids), num_threads)

  def testSlideDatasetInvalid(self, count, window_size, window_shift,
                              window_stride):
    count_t = array_ops.placeholder(dtypes.int64, shape=[])
    window_size_t = array_ops.placeholder(dtypes.int64, shape=[])
    window_shift_t = array_ops.placeholder(dtypes.int64, shape=[])
    window_stride_t = array_ops.placeholder(dtypes.int64, shape=[])

    iterator = dataset_ops.make_initializable_iterator(
        dataset_ops.Dataset.range(10).map(lambda x: x).repeat(count_t).apply(
            sliding.sliding_window_batch(
                window_size=window_size_t,
                window_shift=window_shift_t,
                window_stride=window_stride_t)))
    init_op = iterator.initializer

    with self.cached_session() as sess:
      with self.assertRaises(errors.InvalidArgumentError):
        sess.run(
            init_op,
            feed_dict={
                count_t: count,
                window_size_t: window_size,
                window_shift_t: window_shift,
                window_stride_t: window_stride
            })

  def testTFRecordDatasetFromDataset(self):
    filenames = []
    all_contents = []
    for i in range(_NUM_FILES):
      filename = os.path.join(self.get_temp_dir(), 'tf_record.%d' % i)
      filenames.append(filename)
      writer = python_io.TFRecordWriter(filename)
      for j in range(_NUM_ENTRIES):
        record = compat.as_bytes('Record %d of file %d' % (j, i))
        writer.write(record)
        all_contents.append(record)
      writer.close()

    filenames = dataset_ops.Dataset.from_tensor_slices(filenames)

    dataset = datasets.StreamingFilesDataset(filenames, filetype='tfrecord')

    with ops.device(self._worker_device):
      iterator = dataset_ops.make_initializable_iterator(dataset)
    self._sess.run(iterator.initializer)
    get_next = iterator.get_next()

    retrieved_values = []
    for _ in range(4 * len(all_contents)):
      retrieved_values.append(compat.as_bytes(self._sess.run(get_next)))

    self.assertEqual(set(all_contents), set(retrieved_values))

  def testArbitraryReaderFunc(self):

    def MakeRecord(i, j):
      return compat.as_bytes('%04d-%04d' % (i, j))

    record_bytes = len(MakeRecord(10, 200))

    all_contents = []
    for i in range(_NUM_FILES):
      filename = os.path.join(self.get_temp_dir(), 'fixed_length.%d' % i)
      with open(filename, 'wb') as f:
        for j in range(_NUM_ENTRIES):
          record = MakeRecord(i, j)
          f.write(record)
          all_contents.append(record)

    def FixedLengthFile(filename):
      return readers.FixedLengthRecordDataset(filename, record_bytes)

    dataset = datasets.StreamingFilesDataset(
        os.path.join(self.get_temp_dir(), 'fixed_length*'),
        filetype=FixedLengthFile)

    with ops.device(self._worker_device):
      iterator = dataset_ops.make_initializable_iterator(dataset)
    self._sess.run(iterator.initializer)
    get_next = iterator.get_next()

    retrieved_values = []
    for _ in range(4 * len(all_contents)):
      retrieved_values.append(compat.as_bytes(self._sess.run(get_next)))

    self.assertEqual(set(all_contents), set(retrieved_values))

  def _benchmarkRangeHelper(self, modeling_enabled):
    num_elements = 10000000 if modeling_enabled else 50000000

    # Use `Dataset.skip()` and `Dataset.take()` to perform the iteration in
    # C++, and focus on the minimal overheads (excluding Python invocation
    # costs).
    dataset = dataset_ops.Dataset.range(num_elements).skip(
        num_elements - 1).take(1)
    options = dataset_ops.Options()
    options.experimental_autotune = modeling_enabled
    options.experimental_optimization.apply_default_optimizations = False
    dataset = dataset.with_options(options)
    iterator = dataset_ops.make_initializable_iterator(dataset)
    next_element = iterator.get_next()

    with session.Session() as sess:
      # Run once to warm up the session caches.
      sess.run(iterator.initializer)
      sess.run(next_element)

      # Run once for timing.
      sess.run(iterator.initializer)
      start = time.time()
      sess.run(next_element)
      end = time.time()

      time_per_element = (end - start) / num_elements
      self.report_benchmark(
          iters=num_elements,
          wall_time=time_per_element,
          name="modeling_%s" % ("on" if modeling_enabled else "off"))

  def test_assert_wrong_partial_element_shape_on_unknown_shape_dataset(self):

    def create_unknown_shape_dataset(x):
      return script_ops.py_func(
          lambda _: (  # pylint: disable=g-long-lambda
              np.ones(2, dtype=np.float32),
              np.zeros((3, 4), dtype=np.int32)),
          [x],
          [dtypes.float32, dtypes.int32])

    dataset = dataset_ops.Dataset.range(3).map(create_unknown_shape_dataset)
    unknown_shapes = (tensor_shape.TensorShape(None),
                      tensor_shape.TensorShape(None))
    self.assertEqual(unknown_shapes, dataset.output_shapes)

    wrong_shapes = (tensor_shape.TensorShape(2),
                    tensor_shape.TensorShape((None, 10)))
    iterator = dataset_ops.make_initializable_iterator(
        dataset.apply(batching.assert_element_shape(wrong_shapes)))
    init_op = iterator.initializer
    get_next = iterator.get_next()
    with self.cached_session() as sess:
      sess.run(init_op)
      with self.assertRaises(errors.InvalidArgumentError):
        sess.run(get_next)

  def test_assert_partial_element_shape(self):

    def create_dataset(_):
      return (array_ops.ones(2, dtype=dtypes.float32),
              array_ops.zeros((3, 4), dtype=dtypes.int32))

    dataset = dataset_ops.Dataset.range(5).map(create_dataset)
    partial_expected_shape = (
        tensor_shape.TensorShape(None),  # Unknown shape
        tensor_shape.TensorShape((None, 4)))  # Partial shape
    result = dataset.apply(
        batching.assert_element_shape(partial_expected_shape))
    # Partial shapes are merged with actual shapes:
    actual_shapes = (tensor_shape.TensorShape(2),
                     tensor_shape.TensorShape((3, 4)))
    self.assertEqual(actual_shapes, result.output_shapes)

    iterator = dataset_ops.make_initializable_iterator(result)
    init_op = iterator.initializer
    get_next = iterator.get_next()
    with self.cached_session() as sess:
      sess.run(init_op)
      for _ in range(5):
        sess.run(get_next)
      with self.assertRaises(errors.OutOfRangeError):
        sess.run(get_next)

  def testMapAndBatchSparse(self, numa_aware):

    def _sparse(i):
      return sparse_tensor.SparseTensorValue(
          indices=[[0]], values=(i * [1]), dense_shape=[1])

    dataset = dataset_ops.Dataset.range(10).apply(
        batching.map_and_batch(_sparse, 5))
    if numa_aware:
      options = dataset_ops.Options()
      options.experimental_numa_aware = True
      dataset = dataset.with_options(options)
    iterator = dataset_ops.make_initializable_iterator(dataset)

    init_op = iterator.initializer
    get_next = iterator.get_next()

    with self.cached_session() as sess:
      self.evaluate(init_op)
      for i in range(2):
        actual = self.evaluate(get_next)
        expected = sparse_tensor.SparseTensorValue(
            indices=[[0, 0], [1, 0], [2, 0], [3, 0], [4, 0]],
            values=[i * 5, i * 5 + 1, i * 5 + 2, i * 5 + 3, i * 5 + 4],
            dense_shape=[5, 1])
        self.assertTrue(sparse_tensor.is_sparse(actual))
        self.assertSparseValuesEqual(actual, expected)
      with self.assertRaises(errors.OutOfRangeError):
        self.evaluate(get_next)