How to slice the nth column of a list of lists?

Question

I want to slice the the nth column of a list of lists. e.g.

matrix = [
    ["c","b","a","c"],
    ["d","a","f","d"],
    ["g","h","i","a"]
]
Copy

Do i need to transpose the list and then use indices? e.g.

transposed = []
for i in range(len(matrix)+1):
   transposed.append([row[i] for row in matrix])
transposed[1]
>>> ['b','a','h']
Copy

or is there a way to use indices directly on the nested list?

I was trying something like:

matrix[:][1]
>>>['d','a','f','d']
Copy

but this does not work as I found out.

Thank you

Answer 1

You could use zip to transpose your matrix:

list(zip(*matrix))[1]
Copy

Output: ('b', 'a', 'h')