Python – Convert tuple list to dictionary with key from a given start value
Given a tuple list, the following article focuses on how to convert it to a dictionary, with keys starting from a specified start value. This start value is only to give a head start, next keys will incremented value of their previous keys.
Input : test_list = [(4, 5), (1, 3), (9, 4), (8, 2), (10, 1)], start = 4
Output : {4: (4, 5), 5: (1, 3), 6: (9, 4), 7: (8, 2), 8: (10, 1)}
Explanation : Tuples indexed starting key count from 4.
Input : test_list = [(4, 5), (1, 3), (9, 4), (8, 2), (10, 1)], start = 6
Output : {6: (4, 5), 7: (1, 3), 8: (9, 4), 9: (8, 2), 10: (10, 1)}
Explanation : Tuples indexed starting key count from 6.
Method 1 : Using loop
In this we construct the dictionary by iterating through each tuple and adding its position index, starting from start, as key – value pair in dictionary.
Python3
# initializing list test_list = [( 4 , 5 ), ( 1 , 3 ), ( 9 , 4 ), ( 8 , 2 ), ( 10 , 1 )] # printing original list print ( "The original list is : " + str (test_list)) # initializing start start = 4 res = dict () for sub in test_list: # assigning positional index res[start] = sub start + = 1 # printing result print ( "Constructed dictionary : " + str (res)) |
Output:
The original list is : [(4, 5), (1, 3), (9, 4), (8, 2), (10, 1)]
Constructed dictionary : {4: (4, 5), 5: (1, 3), 6: (9, 4), 7: (8, 2), 8: (10, 1)}
Method 2 : Using dict() and enumerate()
In this, we convert tuple list to dictionary using dict(), and indexing is provided using enumerate().
Python3
# initializing list test_list = [( 4 , 5 ), ( 1 , 3 ), ( 9 , 4 ), ( 8 , 2 ), ( 10 , 1 )] # printing original list print ( "The original list is : " + str (test_list)) # initializing start start = 4 res = dict ( enumerate (test_list, start = start)) # printing result print ( "Constructed dictionary : " + str (res)) |
Output:
The original list is : [(4, 5), (1, 3), (9, 4), (8, 2), (10, 1)]
Constructed dictionary : {4: (4, 5), 5: (1, 3), 6: (9, 4), 7: (8, 2), 8: (10, 1)}