tf.compat.v1.data.experimental.make_batched_features_dataset
Returns a Dataset
of feature dictionaries from Example
protos.
tf.compat.v1.data.experimental.make_batched_features_dataset( file_pattern, batch_size, features, reader=None, label_key=None, reader_args=None, num_epochs=None, shuffle=True, shuffle_buffer_size=10000, shuffle_seed=None, prefetch_buffer_size=None, reader_num_threads=None, parser_num_threads=None, sloppy_ordering=False, drop_final_batch=False )
If label_key argument is provided, returns a Dataset
of tuple comprising of feature dictionaries and label.
Example:
serialized_examples = [ features { feature { key: "age" value { int64_list { value: [ 0 ] } } } feature { key: "gender" value { bytes_list { value: [ "f" ] } } } feature { key: "kws" value { bytes_list { value: [ "code", "art" ] } } } }, features { feature { key: "age" value { int64_list { value: [] } } } feature { key: "gender" value { bytes_list { value: [ "f" ] } } } feature { key: "kws" value { bytes_list { value: [ "sports" ] } } } } ]
We can use arguments:
features: { "age": FixedLenFeature([], dtype=tf.int64, default_value=-1), "gender": FixedLenFeature([], dtype=tf.string), "kws": VarLenFeature(dtype=tf.string), }
And the expected output is:
{ "age": [[0], [-1]], "gender": [["f"], ["f"]], "kws": SparseTensor( indices=[[0, 0], [0, 1], [1, 0]], values=["code", "art", "sports"] dense_shape=[2, 2]), }
Args | |
---|---|
file_pattern | List of files or patterns of file paths containing Example records. See tf.io.gfile.glob for pattern rules. |
batch_size | An int representing the number of records to combine in a single batch. |
features | A dict mapping feature keys to FixedLenFeature or VarLenFeature values. See tf.io.parse_example . |
reader | A function or class that can be called with a filenames tensor and (optional) reader_args and returns a Dataset of Example tensors. Defaults to tf.data.TFRecordDataset . |
label_key | (Optional) A string corresponding to the key labels are stored in tf.Examples . If provided, it must be one of the features key, otherwise results in ValueError . |
reader_args | Additional arguments to pass to the reader class. |
num_epochs | Integer specifying the number of times to read through the dataset. If None, cycles through the dataset forever. Defaults to None . |
shuffle | A boolean, indicates whether the input should be shuffled. Defaults to True . |
shuffle_buffer_size | Buffer size of the ShuffleDataset. A large capacity ensures better shuffling but would increase memory usage and startup time. |
shuffle_seed | Randomization seed to use for shuffling. |
prefetch_buffer_size | Number of feature batches to prefetch in order to improve performance. Recommended value is the number of batches consumed per training step. Defaults to auto-tune. |
reader_num_threads | Number of threads used to read Example records. If >1, the results will be interleaved. Defaults to 1 . |
parser_num_threads | Number of threads to use for parsing Example tensors into a dictionary of Feature tensors. Defaults to 2 . |
sloppy_ordering | If True , reading performance will be improved at the cost of non-deterministic ordering. If False , the order of elements produced is deterministic prior to shuffling (elements are still randomized if shuffle=True . Note that if the seed is set, then order of elements after shuffling is deterministic). Defaults to False . |
drop_final_batch | If True , and the batch size does not evenly divide the input dataset size, the final smaller batch will be dropped. Defaults to False . |
Returns | |
---|---|
A dataset of dict elements, (or a tuple of dict elements and label). Each dict maps feature keys to Tensor or SparseTensor objects. |
Raises | |
---|---|
TypeError | If reader is of the wrong type. |
ValueError | If label_key is not one of the features keys. |
© 2020 The TensorFlow Authors. All rights reserved.
Licensed under the Creative Commons Attribution License 3.0.
Code samples licensed under the Apache 2.0 License.
https://www.tensorflow.org/versions/r2.4/api_docs/python/tf/compat/v1/data/experimental/make_batched_features_dataset