What is the inverse function of zip in python?

Question

Possible Duplicate:
A Transpose/Unzip Function in Python

I've used the zip() function from the numpy library to sort tuples and now I have a list containing all the tuples. I had since modified that list and now I would like to restore the tuples so I can use my data. How can I do this?

Answer 1

lst1, lst2 = zip(*zipped_list)

should give you the unzipped list.

*zipped_list unpacks the zipped_list object. it then passes all the tuples from the zipped_list object to zip, which just packs them back up as they were when you passed them in.

so if:

a = [1,2,3]
b = [4,5,6]

then zipped_list = zip(a,b) gives you:

[(1,4), (2,5), (3,6)]

and *zipped_list gives you back

(1,4), (2,5), (3,6)

zipping that with zip(*zipped_list) gives you back the two collections:

[(1, 2, 3), (4, 5, 6)]