Python – Extract records if Kth elements not in List
Given list of tuples, task is to extract all the tuples where Kth index elements are not present in argument list.
Input : test_list = [(5, 3), (7, 4), (1, 3), (7, 8), (0, 6)], arg_list = [6, 8, 8], K = 1
Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.
To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning - Basic Level Course
Output : [(5, 3), (7, 4), (1, 3)]
Explanation : All the elements which have either 6 or 8 at 1st index are removed.
Input : test_list = [(5, 3), (7, 4)], arg_list = [3, 3, 3, 3], K = 1
Output : [(7, 4)]
Explanation : (5, 3) is removed as it has 3 at 1st index.
Method #1 : Using set() + loop
This is one way in which this task can be. In this, we shorten the argument list using set and then efficiently check for Kth index having any element from arg. list and append accordingly.
Python3
# Python3 code to demonstrate working of# Extract records if Kth elements not in List# Using loop # initializing listtest_list = [(5, 3), (7, 4), (1, 3), (7, 8), (0, 6)] # printing original listprint("The original list : " + str(test_list)) # initializing arg. listarg_list = [4, 8, 4] # initializing KK = 1 # Using set() to shorten arg listtemp = set(arg_list) # loop to check for elements and appendres = []for sub in test_list: if sub[K] not in arg_list: res.append(sub) # printing resultprint("Extracted elements : " + str(res)) |
The original list : [(5, 3), (7, 4), (1, 3), (7, 8), (0, 6)] Extracted elements : [(5, 3), (1, 3), (0, 6)]
Method #2 : Using list comprehension + set()
This is yet another way in which this task can be performed. In this, we compile both, task of filtering duplicates using set() and compiling elements using conditionals inside list comprehension.
Python3
# Python3 code to demonstrate working of# Extract records if Kth elements not in List# Using list comprehension + set() # initializing listtest_list = [(5, 3), (7, 4), (1, 3), (7, 8), (0, 6)] # printing original listprint("The original list : " + str(test_list)) # initializing arg. listarg_list = [4, 8, 4] # initializing KK = 1 # Compiling set() and conditionals into single comprehensionres = [(key, val) for key, val in test_list if val not in set(arg_list)] # printing resultprint("Extracted elements : " + str(res)) |
The original list : [(5, 3), (7, 4), (1, 3), (7, 8), (0, 6)] Extracted elements : [(5, 3), (1, 3), (0, 6)]
