5 Best Ways to Display Dates like Aug 5th Using Python’s strftime

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💡 Problem Formulation: Displaying dates in a readable format is a common task in programming. In Python, the strftime method can be used to format dates. If given a date, such as the 5th of August, we want to display it in the format “Aug 5th”. This can be tricky due to the ordinal indicator (‘st’, ‘nd’, ‘rd’, ‘th’). This article demonstrates how to achieve this with different methods using Python’s strftime.

Method 1: Using string formatting and date suffix function

This method involves using Python’s strftime to generate the date components and a custom function to calculate the appropriate date suffix. This is a flexible approach because the custom function can handle any date suffix logic.

Here’s an example:

import datetime

def date_suffix(day):
    return 'th' if 11 <= day <= 13 else {1: 'st', 2: 'nd', 3: 'rd'}.get(day % 10, 'th')

today = datetime.date(2023, 8, 5)
formatted_date = today.strftime('%b %-d') + date_suffix(today.day)
print(formatted_date)

Output: Aug 5th

The code snippet defines a date_suffix function that adds the correct suffix to the day based on English language rules. The strftime is then used to format the month and day, and the function is called to append the correct ordinal indicator to the day.

Method 2: Using an external library

External libraries such as dateutil can handle complex date formatting, including ordinal indicators. This can be an easy and reliable solution when using well-supported packages.

Here’s an example:

from datetime import datetime
from dateutil.relativedelta import relativedelta

def ordinal_suffix(dt):
    return "%d%s" % (dt.day, 'th' if 4 <= dt.day <= 20 else {1: 'st', 2: 'nd', 3: 'rd'}.get(dt.day % 10, 'th'))

date = datetime.now() + relativedelta(day=5)
formatted_date = date.strftime('%b ') + ordinal_suffix(date)
print(formatted_date)

Output: Aug 5th

This code uses the relativedelta from dateutil to get a date object. The ordinal_suffix function calculates the correct ordinal indicator. The formatted date prefix is gained through strftime and then concatenated with the suffix.

Method 3: Concatenating strftime with manual suffix

This method relies on using Python’s strftime to format the date and then manually adding the suffix for the particular day. This works well for static or known dates but is less dynamic.

Here’s an example:

from datetime import datetime

today = datetime(2023, 8, 5)
formatted_date = today.strftime('%b %-d') + 'th'
print(formatted_date)

Output: Aug 5th

The strftime function formats the date, and then ‘th’ is manually added. It’s straightforward but requires manual adjustment for different days and isn’t suitable for dynamic date handling.

Bonus One-Liner Method 4: Utilizing a lambda expression

This approach uses a lambda function within the strftime method to add the appropriate suffix to each part of the date. It’s concise and suitable for one-off scripts.

Here’s an example:

import datetime

today = datetime.date(2023, 8, 5)
formatted_date = f"{today:%b} {today.day}{(lambda x: 'th' if 11<=x<=13 else {1:'st',2:'nd',3:'rd'}.get(x%10, 'th'))(today.day)}"
print(formatted_date)

Output: Aug 5th

A lambda function is defined inline to determine the correct suffix for the day. The date is formatted using an f-string which embeds the lambda function directly into the string template. This makes it a compact one-liner solution.

Summary/Discussion

  • Method 1: Custom Suffix Function. Flexible for all dates. Requires writing and testing a function.
  • Method 2: External Library dateutil. Easy to use with support for many date formats. Adds a dependency to your project.
  • Method 3: Manual Suffix. Simple and quick for single-use or known dates. Not dynamic and requires manual updates.
  • Method 4: Lambda Expression. Compact and contained within one line. Can be less readable due to complexity.