A Keras tensor is a TensorFlow symbolic tensor object,
which we augment with certain attributes that allow us to build a Keras model
just by knowing the inputs and outputs of the model.
For instance, if a, b and c are Keras tensors,
it becomes possible to do:
model = Model(input=[a, b], output=c)
Arguments
shape
A shape tuple (integers), not including the batch size.
For instance, shape=(32,) indicates that the expected input
will be batches of 32-dimensional vectors. Elements of this tuple
can be None; 'None' elements represent dimensions where the shape is
not known.
batch_size
optional static batch size (integer).
name
An optional name string for the layer.
Should be unique in a model (do not reuse the same name twice).
It will be autogenerated if it isn't provided.
dtype
The data type expected by the input, as a string
(float32, float64, int32...)
sparse
A boolean specifying whether the placeholder to be created is
sparse. Only one of 'ragged' and 'sparse' can be True. Note that,
if sparse is False, sparse tensors can still be passed into the
input - they will be densified with a default value of 0.
tensor
Optional existing tensor to wrap into the Input layer.
If set, the layer will use the tf.TypeSpec of this tensor rather
than creating a new placeholder tensor.
ragged
A boolean specifying whether the placeholder to be created is
ragged. Only one of 'ragged' and 'sparse' can be True. In this case,
values of 'None' in the 'shape' argument represent ragged dimensions.
For more information about RaggedTensors, see
this guide.
**kwargs
deprecated arguments support. Supports batch_shape and
batch_input_shape.
Returns
A tensor.
Example:
# this is a logistic regression in Keras
x = Input(shape=(32,))
y = Dense(16, activation='softmax')(x)
model = Model(x, y)
Note that even if eager execution is enabled,
Input produces a symbolic tensor (i.e. a placeholder).
This symbolic tensor can be used with other
TensorFlow ops, as such:
x = Input(shape=(32,))
y = tf.square(x)
Raises
ValueError
If both sparse and ragged are provided.
ValueError
If both shape and (batch_input_shape or batch_shape) are
provided.