Skip to content
Related Articles

Related Articles

Improve Article

Python – Extracting Priority Elements in Tuple List

  • Last Updated : 03 Jul, 2020

Sometimes, while working with Python Records, we can have a problem in which we need to perform extraction of all the priority elements from records, which usually occur as one of the binary element tuple. This kind of problem can have possible application in web development and gaming domains. Let’s discuss certain ways in which this task can be performed.

Input :
test_list = [(7, 1), (3, 2), (4, 6)]
prior_list = [1, 3, 4]
Output : [1, 3, 4]

Input :
test_list = [(7, 3), (3, 4), (1, 6)]
prior_list = [1, 3, 4]
Output : [3, 4, 1]

Method #1 : Using loop
This is brute force approach to solve this problem. In this, we iterate each element of the priority list and check for individual tuple, filter out the matching element and append to list.




# Python3 code to demonstrate working of 
# Extracting Priority Elements in Tuple List
# loop
  
# initializing list
test_list = [(5, 1), (3, 4), (9, 7), (10, 6)]
  
# printing original list
print("The original list is : " + str(test_list))
  
# initializing Priority list 
prior_list = [6, 4, 7, 1]
  
# Extracting Priority Elements in Tuple List
# loop
res = []
for sub in test_list:
    for val in prior_list:
        if val in sub:
            res.append(val)
  
# printing result 
print("The extracted elements are : " + str(res)) 
Output :



The original list is : [(5, 1), (3, 4), (9, 7), (10, 6)]
The extracted elements are : [1, 4, 7, 6]

 

Method #2 : Using List comprehension + index()
The combination of above functions can be used to solve this problem. In this, we perform the task of checking for required element from tuple using index() and priority comparison.




# Python3 code to demonstrate working of 
# Extracting Priority Elements in Tuple List
# Using List comprehension + <code>index()
  
# initializing list
test_list = [(7, 1), (6, 4), (4, 7), (1, 6)]
  
# printing original list
print("The original list is : " + str(test_list))
  
# initializing Priority list 
prior_list = [6, 4, 7, 1]
  
# Extracting Priority Elements in Tuple List
# Using List comprehension + <code>index()
res = [sub[0] if prior_list.index(sub[0]) < prior_list.index(sub[1])
              else sub[1] for sub in test_list]
  
# printing result 
print("The extracted elements are : " + str(res)) 
Output :
The original list is : [(7, 1), (6, 4), (4, 7), (1, 6)]
The extracted elements are : [7, 6, 4, 6]

 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




My Personal Notes arrow_drop_up
Recommended Articles
Page :