Скачать или смотреть How to Count and Print Hourly Occurrences from a Text File in Python

Learn a clean and effective way to extract hours from timestamps in a text file and print each hour with its occurrence count using Python.
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This video is based on the question https://stackoverflow.com/q/79465282/ asked by the user 'Brian Fulton' ( https://stackoverflow.com/u/16855873/ ) and on the answer https://stackoverflow.com/a/79465885/ provided by the user 'SIGHUP' ( https://stackoverflow.com/u/17580381/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

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The Problem

You have a text file with lines containing timestamps, such as email logs, and you want to:

Extract the hour portion from each timestamp.

Count how many times each hour appears.

Print the sorted hourly counts in a specific format.

You may have tried solutions that print tuples or use multiple loops, but the output format often doesn't match the expected one (causing pytest failures).



Concise and Modern Solution

Using Python's built-in tools, you can efficiently parse and count the hours, then print them cleanly:

[[See Video to Reveal this Text or Code Snippet]]

Why This Works

Line filtering: Use startswith("From ") to target relevant lines reliably.

Safe parsing: Try-except ensures errors don't break processing.

Counting: defaultdict(int) simplifies counting occurrences.

Printing format: Printing as hour count with a space matches pytest expectations.

Notes

Make sure the timestamp always exists at the expected position (index 5 here). Adjust indices if your file format differs.

Sorting keys before printing ensures output matches expected ordered results.

Avoid printing tuples directly (print(item) prints ('04', 3)), instead unpack them: print(*item) or formatted print.



With this approach, your code becomes clean, efficient, and aligned with common testing formats.