What dose the operator @ mean in python

Question

I am reading someone's code, where the operator "@" appears (in fact, I am not even sure whether @ is an operator or not).

I searched around, but could not get any clues. I guess it's some advanced usage.

Here is some example code:

hidden = self.adj_norm @ tf.sparse_tensor_dense_matmul(hidden, w) + b

hidden = self.adj_norm @ hidden @ w + b

final_output = self.adj_norm @ tf.sparse_tensor_dense_matmul(final_output, w) + b

final_output = self.adj_norm @ final_output @ w + b

Can somebody explain or provide some references that I can check for the usage of "@"?

What does `+` mean. It depends on what it's applied to. In your case looks like `@` is used as dot product. — Julien, Apr 23 '19 at 05:44

score 5 · Accepted Answer · edited Apr 23 '19 at 07:14

5

Mostly @ is used as a decorator. In your case however, it seems it is used for matrix multiplication.

In python matrix multiplication, x @ y invokes x.__matmul__(y) or:

x @ y
#equivalent to

dot(x, y)
and

x @= y
#equivalent to

x = dot(x, y)

Dot is the matrix multiplication function in Numpy and x and y.

edited Apr 23 '19 at 07:14

Matthias

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answered Apr 23 '19 at 05:49

Yash

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x@y is not equivalent to np.dot(x, y) dot and matmul are different operations – Lesiak Apr 23 '19 at 06:02
is it unique to python 3? I am using python 2.7 – Paradox Apr 23 '19 at 13:56

What dose the operator @ mean in python

1 Answers1