Which function in Tensorflow is similar to expand_as in Pytorch
I am trying to adapt some code from Pytorch to Tensorflow, though I'm not so familiar with the latter. 

I use expand_as in my old code. Is there any similar function which can be used in Tensorflow?

You are looking for tf.broadcast_to which has been introduced in TF 1.9 (initially under the name tf.contrib.framework.broadcast_to).
