How do you rotate an array of strings in Python?

Question

In Python, given the following array of strings,

[   'abc',
    'def',
    'ghi',
    'jkl'
]

how do you transform it so it becomes,

[   'jgda',
    'kheb',
    'lifc'
]

Rakesh · Accepted Answer · 2018-07-17 09:58:58Z

4

Using zip and str.join

Ex:

a = ['abc', 'def', 'ghi', 'jkl']

for i in zip(*a):
    print("".join(i)[::-1])

Output:

jgda
kheb
lifc

answered Jul 17, 2018 at 9:58

Rakesh

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3 Comments

Or list(map(''.join, zip(*reversed(lst))))

@tobias_k Thanks :)

yes, certainly reversing the list first is an improvement, in your syntax would be for i in zip(*a[::-1]): print("".join(i))

FHTMitchell · Accepted Answer · 2018-07-17 10:05:34Z

1

You could use numpy

import numpy as np
x = ['abc',
     'def',
     'ghi',
     'jkl'
  ]

a = np.rot90([list(row) for row in x], 3)
result = [''.join(row) for row in a]

output:

[
 'jgda', 
 'kheb', 
 'lifc'
]

answered Jul 17, 2018 at 10:05

FHTMitchell

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