`x`

in test phase, and `alt`

otherwise.Note that `alt`

should have the *same shape* as `x`

.

`k_in_test_phase(x, alt, training = NULL)`

Either `x`

or `alt`

based on `k_learning_phase()`

.

- x
What to return in test phase (tensor or function that returns a tensor).

- alt
What to return otherwise (tensor or function that returns a tensor).

- training
Optional scalar tensor (or R logical or integer) specifying the learning phase.

This function is part of a set of Keras backend functions that enable lower level access to the core operations of the backend tensor engine (e.g. TensorFlow, CNTK, Theano, etc.).

You can see a list of all available backend functions here: https://tensorflow.rstudio.com/reference/keras/index.html#backend.