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Python: Extract the nth element from a given list of tuples using lambda

Python Lambda: Exercise-36 with Solution

Write a Python program to extract the nth element from a given list of tuples using lambda.

Sample Solution:

Python Code :

def extract_nth_element(test_list, n):
    result = list(map (lambda x:(x[n]), test_list))
    return result
students = [('Greyson Fulton', 98, 99), ('Brady Kent', 97, 96), ('Wyatt Knott', 91, 94), ('Beau Turnbull', 94, 98)] 
print ("Original list:")
print(students)
n = 0
print("\nExtract nth element ( n =",n,") from the said list of tuples:")
print(extract_nth_element(students, n))
n = 2
print("\nExtract nth element ( n =",n,") from the said list of tuples:")
print(extract_nth_element(students, n))

Sample Output:

Original list:
[('Greyson Fulton', 98, 99), ('Brady Kent', 97, 96), ('Wyatt Knott', 91, 94), ('Beau Turnbull', 94, 98)]

Extract nth element ( n = 0 ) from the said list of tuples:
['Greyson Fulton', 'Brady Kent', 'Wyatt Knott', 'Beau Turnbull']

Extract nth element ( n = 2 ) from the said list of tuples:
[99, 96, 94, 98]

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Previous: Write a Python program to check whether a specified list is sorted or not using lambda.
Next: Write a Python program to sort a list of lists by a given index of the inner list using lambda.

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Python: Tips of the Day

Python: Cache results with decorators

There is a great way to cache functions with decorators in Python. Caching will help save time and precious resources when there is an expensive function at hand.

Implementation is easy, just import lru_cache from functools library and decorate your function using @lru_cache.

from functools import lru_cache

@lru_cache(maxsize=None)
def fibo(a):
    if a <= 1:
        return a
    else:
        return fibo(a-1) + fibo(a-2)

for i in range(20):
    print(fibo(i), end="|")

print("\n\n", fibo.cache_info())

Output:

0|1|1|2|3|5|8|13|21|34|55|89|144|233|377|610|987|1597|2584|4181|

 CacheInfo(hits=36, misses=20, maxsize=None, currsize=20)