Python: Find the index of the first element in the given list that satisfies the provided testing function
Python List: Exercise - 229 with Solution
Write a Python program to find the index of the first element in the given list that satisfies the provided testing function.
Use a list comprehension, enumerate() and next() to return the index of the first element in nums for which fn returns True.
Sample Solution:
Python Code:
def find_index(nums, fn):
return next(i for i, x in enumerate(nums) if fn(x))
print(find_index([1, 2, 3, 4], lambda n: n % 2 == 1))
Sample Output:
0
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Previous: Write a Python program to get every element that exists in any of the two given lists once, after applying the provided function to each element of both.
Next: Write a Python program to find the indexes of all elements in the given list that satisfy the provided testing function.
What is the difficulty level of this exercise?
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Python: Tips of the Day
Given a predicate function, fn, and a prop string, this curried function will then take an object to inspect by calling the property and passing it to the predicate:
Example:
def tips_check_prop(fn, prop): return lambda obj: fn(obj[prop]) check_age = tips_check_prop(lambda x: x >= 25, 'age') user = {'name': 'Owen', 'age': 25} print(check_age(user))
Output:
True
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