This seems to be a good way to get the transpose of a matrix. But I'm not sure what exactly is happening when the * operator is invoked. Can someone unpack that?
>>> zip(*[[1,2,3], [4,5,6]])
[(1,4), (2,5), (3,6)]
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It's list unpacking: http://stackoverflow.com/questions/3480184/unpack-a-list-in-python – NightShadeQueen Jul 01 '15 at 17:16
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It is covered in the tutorial: [Unpacking Argument Lists](https://docs.python.org/2/tutorial/controlflow.html#unpacking-argument-lists). Python 3.5 implements [PEP 0448 -- Additional Unpacking Generalizations](https://www.python.org/dev/peps/pep-0448/). – jfs Jul 01 '15 at 17:17
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1I tried actually searching for this and found a chain of duplicates so long I gave up looking for the first one. Please search first. This **exact question** has literally been answered dozens of times here. – Two-Bit Alchemist Jul 01 '15 at 17:18
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1Can someone *unpack* that? Ha! – Malik Brahimi Jul 01 '15 at 17:39
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It's the splat operator. Basically, it passes the contents of the lists as arguments. – Malik Brahimi Jul 01 '15 at 17:40
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So `zip(*[[1,2,3], [4,5,6]])` is the same `zip([1,2,3], [4,5,6])` – Malik Brahimi Jul 01 '15 at 17:41
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Haha @MalikBrahimi I'm glad I'm not the only one who laughed at that. – Two-Bit Alchemist Jul 01 '15 at 18:50
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The * operator is used to unpack the values, when using that in the list of lists like - zip(*[[1,2,3], [4,5,6]]) , it unpacks the outer list, and hence the actual input to zip function looks like - zip([1,2,3], [4,5,6]) . And when they get zipped you get the result - [(1,4), (2,5), (3,6)]
Anand S Kumar
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