tf.keras.backend.cast

tf.keras.backend.cast(
    x,
    dtype
)

Defined in tensorflow/python/keras/_impl/keras/backend.py.

Casts a tensor to a different dtype and returns it.

You can cast a Keras variable but it still returns a Keras tensor.

Arguments:

• x: Keras tensor (or variable).
• dtype: String, either ('float16', 'float32', or 'float64').

Returns:

Keras tensor with dtype `dtype`.

Example:

>>> from keras import backend as K
>>> input = K.placeholder((2, 3), dtype='float32')
>>> input
<tf.Tensor 'Placeholder_2:0' shape=(2, 3) dtype=float32>
# It doesn't work in-place as below.
>>> K.cast(input, dtype='float16')
<tf.Tensor 'Cast_1:0' shape=(2, 3) dtype=float16>
>>> input
<tf.Tensor 'Placeholder_2:0' shape=(2, 3) dtype=float32>
# you need to assign it.
>>> input = K.cast(input, dtype='float16')
>>> input
<tf.Tensor 'Cast_2:0' shape=(2, 3) dtype=float16>