tensorflow/models · error · ValueError

TransformerScaffold expects a three-dimensional input of sha

Error message

TransformerScaffold expects a three-dimensional input of shape [batch, sequence, width].

What it means

Error "TransformerScaffold expects a three-dimensional input of shape [batch, sequence, width]." thrown in tensorflow/models.

Source

Thrown at official/nlp/modeling/layers/transformer_scaffold.py:138

    self._kernel_initializer = tf_keras.initializers.get(kernel_initializer)
    self._bias_initializer = tf_keras.initializers.get(bias_initializer)
    self._kernel_regularizer = tf_keras.regularizers.get(kernel_regularizer)
    self._bias_regularizer = tf_keras.regularizers.get(bias_regularizer)
    self._kernel_constraint = tf_keras.constraints.get(kernel_constraint)
    self._bias_constraint = tf_keras.constraints.get(bias_constraint)

  def build(self, input_shape):
    if isinstance(input_shape, tf.TensorShape):
      input_tensor_shape = input_shape
    elif isinstance(input_shape, (list, tuple)):
      input_tensor_shape = tf.TensorShape(input_shape[0])
    else:
      raise ValueError(
          "The type of input shape argument is not supported, got: %s" %
          type(input_shape))

    if len(input_tensor_shape.as_list()) != 3:
      raise ValueError(
          "TransformerScaffold expects a three-dimensional input of "
          "shape [batch, sequence, width].")
    hidden_size = input_tensor_shape[-1]
    if hidden_size % self._num_heads != 0:
      raise ValueError(
          "The input size (%d) is not a multiple of the number of attention "
          "heads (%d)" % (hidden_size, self._num_heads))
    self._attention_head_size = int(hidden_size // self._num_heads)

    common_kwargs = dict(
        kernel_regularizer=self._kernel_regularizer,
        bias_regularizer=self._bias_regularizer,
        activity_regularizer=self._activity_regularizer,
        kernel_constraint=self._kernel_constraint,
        bias_constraint=self._bias_constraint)

    def get_layer_instance(instance_or_cls, config, default_config):
      if isinstance(instance_or_cls, tf_keras.layers.Layer):

View on GitHub (pinned to e006f5f0d5)

When it happens

Trigger: Thrown at official/nlp/modeling/layers/transformer_scaffold.py:138 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of tensorflow/models@e006f5f0d5 (2026-08-24). Data as JSON: /api/errors/5b19a73ea5929a1a. Report an issue: GitHub.