Python – Sort Records by Kth Index List

• Last Updated : 02 Sep, 2021

Sometimes, while working with Python Records, we can have a problem in which we need to perform Sorting of Records by some element in Tuple, this can again be sometimes, a list and sorting has to performed by Kth index of that list. This is uncommon problem, but can have usecase in domains such as web development. Let’s discuss certain way in which this task can be performed.

Input
test_list = [([4, 5], ‘Gfg’), ([8, 4], ‘is’), ([2, 3], ‘best’)]
K = 0
Output : [([2, 3], ‘best’), ([4, 5], ‘Gfg’), ([8, 4], ‘is’)]
Input
test_list = [([4, 5], ‘Gfg’), ([8, 4], ‘is’), ([2, 3], ‘best’)]
K = 1
Output : [([2, 3], ‘best’), ([8, 4], ‘is’), ([4, 5], ‘Gfg’)]

Method : Using sort() + lambda
The combination of above functions can be used to solve this problem. In this, we perform the task of sorting using sort, the parameter and index by which sorting has to be performed is provided using lambda function.

Python3

 `# Python3 code to demonstrate working of``# Sort Records by Kth Index List``# Using sort() + lambda` `# initializing list``test_list ``=` `[([``4``, ``5``, ``7``, ``3``], ``'Gfg'``), ([``8``, ``6``, ``3``, ``1``], ``'is'``),``                                 ``([``2``, ``3``, ``5``, ``2``], ``'best'``)]` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))` `# initializing K``K ``=` `1` `# Sort Records by Kth Index List``# Using sort() + lambda``test_list.sort(key ``=` `lambda` `sub: sub[``0``][K])` `# printing result``print``(``"The records after sorting : "` `+` `str``(test_list))`

Output :

The original list is : [([4, 5, 7, 3], ‘Gfg’), ([8, 6, 3, 1], ‘is’), ([2, 3, 5, 2], ‘best’)]
The records after sorting : [([2, 3, 5, 2], ‘best’), ([4, 5, 7, 3], ‘Gfg’), ([8, 6, 3, 1], ‘is’)]

My Personal Notes arrow_drop_up