vec = [[1,2,3], [4,5,6], [7,8,9]]
print [num for elem in vec for num in elem] <----- this
>>> [1, 2, 3, 4, 5, 6, 7, 8, 9]
This is tricking me out.
I understand elem is the lists inside of the list from for elem in vic
I don't quite understand the usage of num
and for num in elem
in the beginning and the end.
How does python interpret this?
What's the order it looks at?