Dictionary with index as value in Python

In this article we will learn how to create a dictionary from another frequently used python collection namely list. An index or key is not part a list content. But in dictionary we need to have a key or index attached to every element which is referred as value.

Using enumerate

The enumerate function adds a counter as the key of the enumerate object. SO we apply it to a given list and using a for loop. That creates the required dictionary where the keys are generated by the enumerate function.

Example

Alist = ['Mon', 'Tue', 'Wed', 'Wed',11,11]

# Given list
print("Given list : " , Alist)

# Converting to DIctionary
NewDict = {val: key + 1 for key, val in enumerate(Alist)}

# print result
print("Dictionary created with index : ",NewDict)

Output

Running the above code gives us the following result −

Given list : ['Mon', 'Tue', 'Wed', 'Wed', 11, 11]
Dictionary created with index : {'Mon': 1, 'Tue': 2, 'Wed': 4, 11: 6}

Please note when there are duplicate elements only them is displayed having a higher index value from among the duplicates.

Using zip and range

Another approach is to apply the range function to create the keys starting from 1 and going up to the length of the list supplied. Finally, we apply the dict function to create the dictionary.

Example

Alist = ['Mon', 'Tue', 'Wed', 'Wed',11,11]

# Given list
print("Given list : " , Alist)

# Converting to DIctionary
NewDict = dict(zip(Alist, range(1, len(Alist)+1)))

# print result
print("Dictionary created with index : ",NewDict)

Output

Running the above code gives us the following result −

Given list : ['Mon', 'Tue', 'Wed', 'Wed', 11, 11]
Dictionary created with index : {'Mon': 1, 'Tue': 2, 'Wed': 4, 11: 6}