Python program to filter future dates

Last update on December 21 2024 07:30:03 (UTC/GMT +8 hours)

Write a Python program that implements a Python program that filters out dates (in the format "YYYY-MM-DD") that are in the future using the filter function.

Sample Solution:

Python Code:

from datetime import datetime

# Define a list of dates in "YYYY-MM-DD" format
date_strings = ["2023-07-11", "2022-02-22", "2024-05-11", "2025-12-31", "2021-01-01"]
print("List of dates:")
print(date_strings)
# Convert the date strings to datetime objects
dates = [datetime.strptime(date, "%Y-%m-%d") for date in date_strings]

# Get the current date
current_date = datetime.now()
print("Current date:",current_date)

# Define a function to check if a date is in the future
def is_date_in_future(date):
    return date > current_date

# Use the filter function to extract dates in the past
dates_in_past = list(filter(is_date_in_future, dates))

# Convert the filtered dates back to strings
filtered_date_strings = [date.strftime("%Y-%m-%d") for date in dates_in_past]
print("\nCheck if a date is in the future!")
# Print the dates in the past
print(filtered_date_strings)

Explanation:

In the exercise above -

• First, we start with a list of date strings in the "YYYY-MM-DD" format.
• Convert date strings to datetime objects using datetime.strptime.
• We get the current date and time using datetime.now().
• Define a function "is_date_in_future()" that checks if a date is in the future by comparing it with the current date.
• Use the filter function to filter out dates in the future from the dates list by applying the "is_date_in_future()" function as the filtering condition.
• The filtered datetime objects are then converted back to date strings using strftime with the "YYYY-MM-DD" format.
• Finally, we print the dates in the future.

Sample Output:

List of dates:
['2023-07-11', '2022-02-22', '2024-05-11', '2025-12-31', '2021-01-01']
Current date: 2023-09-30 10:04:30.206035

Check if a date is in the future!
['2024-05-11', '2025-12-31']

Flowchart:

Python Code Editor:

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