Python Program to Filter Rows with a specific Pair Sum

When it is required to filter rows with a specific pair sum, a method is defined. It checks to see if elements in a specific index is equal to key, and returns output based on this.

Below is a demonstration of the same −

Example

 Live Demo

def find_sum_pair(val, key):    for index in range(len(val)):       for ix in range(index + 1, len(val)):          if val[index] + val[ix] == key:             return True    return False my_list = [[71, 5, 21, 6], [34, 21, 2, 71], [21, 2, 34, 5], [6, 9, 21, 42]] print("The list is :") print(my_list) my_key = 76 print("The key is ") print(my_key) my_result = [element for element in my_list if find_sum_pair(element, my_key)] print("The resultant list is :") print(my_result)

Output

The list is : [[71, 5, 21, 6], [34, 21, 2, 71], [21, 2, 34, 5], [6, 9, 21, 42]] The key is 76 The resultant list is : [[71, 5, 21, 6]]

Explanation

• A method named 'find_sum_pair' is defined that takes two parameters.

• It iterates through the first parameter, and checks to see if elements in sum of values in two specific indices are equal to the second parameter.

• If yes, the 'True' value is returned.

• Otherwise, 'False' is returned.

• Outside the method, a list of list is defined and is displayed on the console.

• A value for key is defined.

• The list comprehension is used to iterate over the list and the method is called by passing the required parameters.

• This is assigned to a variable.

• It is displayed as output on the console.