Python Index Ranks of Elements

When it is required to determine the index rank of elements in a data structure, a method is defined that takes a list as a parameter. It iteeates over the elements in the list, and performs certain comparisons before changing the values of two variables.

Example

Below is a demonstration of the same

def find_rank_elem(my_list):
   my_result = [0 for x in range(len(my_list))]
   for elem in range(len(my_list)):
      (r, s) = (1, 1)
      for j in range(len(my_list)):
         if j != elem and my_list[j] < my_list[elem]:
            r += 1
         if j != elem and my_list[j] == my_list[elem]:
            s += 1

      my_result[elem] = r + (s - 1) / 2

   return my_result

my_list = [1, 3, 5, 3, 1, 26, 99, 45, 67, 12]
print("The list is :")
print(my_list)
print("The resultant list is :")
print(find_rank_elem(my_list))

Output

The list is :
[1, 3, 5, 3, 1, 26, 99, 45, 67, 12]
The resultant list is :
[1, 3, 5, 3, 1, 7, 10, 8, 9, 6]

Explanation

• A method named ‘find_rank_elem’ is defined that takes a list as a parameter.

• The list is iterated over and stored in a list variable.

• It is again iterated over, and checked to see if certain elements of the list match.

• If they do, two values ‘r’ and ‘s’ are changed.

• This list is returned as output.

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

• The method is called by passing this list as a parameter.

• The output is displayed on the console.