Python: Creates a dictionary with the same keys as the given dictionary and values generated by running the given function for each value

Last update on June 28 2025 12:41:17 (UTC/GMT +8 hours)

74. Create Dictionary with Same Keys and Function-Transformed Values

Write a Python program to create a dictionary with the same keys as the given dictionary and values generated by running the given function for each value.

Sample Solution:

Python Code:

# Define a function 'test' that takes a dictionary 'obj' and a function 'fn'.
def test(obj, fn):
    # Use a dictionary comprehension to apply the function 'fn' to each value in the 'obj' dictionary.
    # The result is a new dictionary with the same keys, where each value is transformed by 'fn'.
    return dict((k, fn(v)) for k, v in obj.items())

# Create a dictionary 'users' where each key corresponds to a user and has associated data as a dictionary.
users = {
    'Theodore': {'user': 'Theodore', 'age': 45},
    'Roxanne': {'user': 'Roxanne', 'age': 15},
    'Mathew': {'user': 'Mathew', 'age': 21},
}

# Print the original dictionary elements.
print("\nOriginal dictionary elements:")
print(users)

# Call the 'test' function to create a new dictionary with the same keys, but with 'age' values extracted.
print("\nDictionary with the same keys:")
print(test(users, lambda u: u['age'])) 

Sample Output:

Original dictionary elements:
{'Theodore': {'user': 'Theodore', 'age': 45}, 'Roxanne': {'user': 'Roxanne', 'age': 15}, 'Mathew': {'user': 'Mathew', 'age': 21}}

Dictionary with the same keys:
{'Theodore': 45, 'Roxanne': 15, 'Mathew': 21}

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to apply a given function to each value of a dictionary and return a new dictionary with the same keys and transformed values.
• Write a Python program to use dictionary comprehension to map over a dictionary's values with a provided function.
• Write a Python program to implement a function that takes a dictionary and a transformation function, returning a new dictionary with updated values.
• Write a Python program to combine lambda functions with dictionary comprehension to modify all values in a dictionary.

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