tf.sequence_mask

tf.sequence_mask

tf.sequence_mask

sequence_mask(
    lengths,
    maxlen=None,
    dtype=tf.bool,
    name=None
)

Defined in tensorflow/python/ops/array_ops.py.

See the guide: Tensor Transformations > Slicing and Joining

Return a mask tensor representing the first N positions of each row.

Example:

tf.sequence_mask([1, 3, 2], 5) =
  [[True, False, False, False, False],
   [True, True, True, False, False],
   [True, True, False, False, False]]

Args:

• lengths: 1D integer tensor, all its values < maxlen.
• maxlen: scalar integer tensor, maximum length of each row. Default: use maximum over lengths.
• dtype: output type of the resulting tensor.
• name: name of the op.

Returns:

A 2D mask tensor, as shown in the example above, cast to specified dtype.

Raises:

• ValueError: if the arguments have invalid rank.