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tf.keras.backend.placeholder

TensorFlow 2.0 version View source on GitHub

Instantiates a placeholder tensor and returns it.

Aliases:

  • tf.compat.v1.keras.backend.placeholder
  • tf.compat.v2.keras.backend.placeholder
tf.keras.backend.placeholder(
    shape=None,
    ndim=None,
    dtype=None,
    sparse=False,
    name=None
)

Arguments:

  • shape: Shape of the placeholder (integer tuple, may include None entries).
  • ndim: Number of axes of the tensor. At least one of {shape, ndim} must be specified. If both are specified, shape is used.
  • dtype: Placeholder type.
  • sparse: Boolean, whether the placeholder should have a sparse type.
  • name: Optional name string for the placeholder.

Raises:

  • ValueError: If called with eager execution.

Returns:

Tensor instance (with Keras metadata included).

Examples:

    >>> from keras import backend as K
    >>> input_ph = K.placeholder(shape=(2, 4, 5))
    >>> input_ph
    <tf.Tensor 'Placeholder_4:0' shape=(2, 4, 5) dtype=float32>