What does tf.nn.embedding_lookup function do?

Question

tf.nn.embedding_lookup(params, ids, partition_strategy=\'mod\', name=None)

I cannot understand the duty of this function. Is it like a lookup table

Answer 1

Here's an image depicting the process of embedding lookup.

Concisely, it gets the corresponding rows of a embedding layer, specified by a list of IDs and provide that as a tensor. It is achieved through the following process.

1. Define a placeholder lookup_ids = tf.placeholder([10])
2. Define a embedding layer embeddings = tf.Variable([100,10],...)
3. Define the tensorflow operation embed_lookup = tf.embedding_lookup(embeddings, lookup_ids)
4. Get the results by running lookup = session.run(embed_lookup, feed_dict={lookup_ids:[95,4,14]})