Given Matrix, extract all rows whose all elements have a frequency greater than K.
Input : test_list = [[1, 1, 2, 3, 2, 3], [4, 4, 5, 6, 6], [1, 1, 1, 1], [4, 5, 6, 8]], K = 2
Output : [[1, 1, 1, 1]]
Explanation : Here, frequency of 1 is 4 > 2, hence row retained.Input : test_list = [[1, 1, 2, 3, 2, 3], [4, 4, 5, 6, 6], [1, 3, 4, 1], [4, 5, 6, 8]], K = 2
Output : []
Explanation : No list filtered as result.
Method #1 : Using list comprehension + all() + count()
In this, we perform task of iterating through elements using list comprehension and all() is used to check for each elements count(), extracted using count().
Python3
# Python3 code to demonstrate working of # Rows with all Elements frequency greater than K# Using list comprehension + count() + all() def freq_greater_K(row, K) : # checking for all elements occurrence greater than K return all(row.count(ele) > K for ele in row) # initializing listtest_list = [[1, 1, 2, 3, 2, 3], [4, 4, 5, 6, 6], [1, 1, 1, 1], [4, 5, 6, 8]] # printing original listprint("The original list is : " + str(test_list)) # initializing K K = 1 # checking for each row res = [ele for ele in test_list if freq_greater_K(ele, K)] # printing result print("Filtered rows : " + str(res)) |
Output:
The original list is : [[1, 1, 2, 3, 2, 3], [4, 4, 5, 6, 6], [1, 1, 1, 1], [4, 5, 6, 8]]
Filtered rows : [[1, 1, 2, 3, 2, 3], [1, 1, 1, 1]]
Method #2 : Using filter() + lambda + all() + count()
In this, task of filtering is done using filter() + lambda, all() is used to check for each element, count() to compute count.
Python3
# Python3 code to demonstrate working of # Rows with all Elements frequency greater than K# Using filter() + lambda + all() + count() def freq_greater_K(row, K) : # checking for all elements occurrence greater than K return all(row.count(ele) > K for ele in row) # initializing listtest_list = [[1, 1, 2, 3, 2, 3], [4, 4, 5, 6, 6], [1, 1, 1, 1], [4, 5, 6, 8]] # printing original listprint("The original list is : " + str(test_list)) # initializing K K = 1 # checking for each row res = list(filter(lambda ele : freq_greater_K(ele, K), test_list)) # printing result print("Filtered rows : " + str(res)) |
Output:
The original list is : [[1, 1, 2, 3, 2, 3], [4, 4, 5, 6, 6], [1, 1, 1, 1], [4, 5, 6, 8]]
Filtered rows : [[1, 1, 2, 3, 2, 3], [1, 1, 1, 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
