tf.data.experimental.group_by_window
A transformation that groups windows of elements by key and reduces them.
tf.data.experimental.group_by_window(
key_func, reduce_func, window_size=None, window_size_func=None
)
This transformation maps each consecutive element in a dataset to a key using key_func and groups the elements by key. It then applies reduce_func to at most window_size_func(key) elements matching the same key. All except the final window for each key will contain window_size_func(key) elements; the final window may be smaller.
You may provide either a constant window_size or a window size determined by the key through window_size_func.
| Args | |
|---|---|
key_func |
A function mapping a nested structure of tensors (having shapes and types defined by self.output_shapes and self.output_types) to a scalar tf.int64 tensor. |
reduce_func |
A function mapping a key and a dataset of up to window_size consecutive elements matching that key to another dataset. |
window_size |
A tf.int64 scalar tf.Tensor, representing the number of consecutive elements matching the same key to combine in a single batch, which will be passed to reduce_func. Mutually exclusive with window_size_func. |
window_size_func |
A function mapping a key to a tf.int64 scalar tf.Tensor, representing the number of consecutive elements matching the same key to combine in a single batch, which will be passed to reduce_func. Mutually exclusive with window_size. |
| Returns | |
|---|---|
A Dataset transformation function, which can be passed to tf.data.Dataset.apply. |
| Raises | |
|---|---|
ValueError |
if neither or both of {window_size, window_size_func} are passed. |
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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/data/experimental/group_by_window