Python List of Tuples into Dictionary

How to convert a list of tuples to a dictionary in Python? In Python, a list of tuples can be converted into a dictionary by using various methods. Converting a list of tuples into a dictionary can be useful in situations where you have data that is organized as key-value pairs, but it is easier to work with as a dictionary. This conversion can make the data more readable and easier to manipulate, as dictionaries allow you to access values by their corresponding keys.

You can convert a list of tuples to a dictionary in Python using many ways, for example, by using the dict(), for loop, dict comprehension, setdefault(), itertools.groupby(), dict() constructor, and list comprehension. In this article, I will explain how to convert a list of tuples to a dictionary by using all these functions with examples.

1. Quick Examples of Converting List of Tuples To Dictionary

If you are in a hurry, below are some quick examples of converting a list of tuples into a dictionary.


# Quick examples of converting list of tuples into dictionary

# list of tuples
list_tuples = [("Python", 2000), ("Spark", 2500), ("Pandas", 3000)]

# Example 1: Convert a list of tuples to a dictionary
mydict = dict(list_tuples)

# Example 2: Convert to dictionary using a for loop
mydict = {}
for item in list_tuples:
    key = item[0]
    value = item[1]
    mydict[key] = value

# Example 3: Convert a list of tuples to a dictionary
# Using dictionary comprehension
mydict = {tup[0]: tup[1] for tup in list_tuples}

# Example 4: Using dictionary comprehension
mydict = {key: value for (key, value) in list_tuples}

# Example 5: Convert to dictionary 
# Using setdefault() method
mydict = {}
for key, val in list_tuples:
    mydict.setdefault(key, val)

# Example 6: Using the dict() constructor and a list comprehension
def convert_to_dict(list_tuples):
    dictionary = dict((key, value) for key, value in list_tuples)
    return dictionary 

# Example 7: Using itertools.groupby() function
def convert_to_dict(list_tuples):
    groups = groupby(list_tuples, key=lambda x: x[0])
    dictionary = {}
    # Iterate over the groups
    for key, group in groups:
        dictionary[key] = [tuple[1] for tuple in group]
    return dictionary

2. Convert a List of Tuples to a Dictionary in Python

You can convert a list of tuples into a dictionary using the built-in dict() function. For example, you have a list of tuples list_tuples containing course names and their corresponding quantities. Then you can use the dict() function to convert this list to a dictionary mydict. The keys of the dictionary are the first elements of the tuples in the list, and the values are the second element of the tuples.


# list of tuples
list_tuples = [("Python", 2000), ("Spark", 2500), ("Pandas", 3000)]
print("Orginal list of tuples: ",list_tuples)

# Convert a list of tuples to a dictionary
mydict = dict(list_tuples)
print("List of tuples into dictionary:", mydict)

Yields below output.

3. Convert a List of Tuples to a Dictionary Using For Loop

To convert a list of tuples to a dictionary in Python using a for loop. For instance, first, you can initialize an empty dictionary mydict. Then, you can iterate over each item in the list using a for loop. For each item, you can extract the first element of the tuple as the key and the second element as the value. Finally, you can add the key-value pair to the dictionary using the syntax mydict[key] = value. At the end of the loop, the mydict dictionary contains the same key-value pairs as the original list_tuples list of tuples.


# list of tuples
list_tuples = [("Python", 2000), ("Spark", 2500), ("Pandas", 3000)]
print("Orginal list of tuples: ",list_tuples)

# Convert list of tuples to dictionary using a for loop
mydict = {}
for item in list_tuples:
    key = item[0]
    value = item[1]
    mydict[key] = value
print("List of tuples into dictionary:", mydict)