Скачать или смотреть How to Randomly Select Unique Values in Python with while Loops

Discover how to effectively select random values in Python while ensuring they remain unique, avoiding redundancy with simple techniques and best practices.
---
This video is based on the question https://stackoverflow.com/q/77943210/ asked by the user 'Saeed' ( https://stackoverflow.com/u/5790653/ ) and on the answer https://stackoverflow.com/a/77943307/ provided by the user 'Tim Roberts' ( https://stackoverflow.com/u/1883316/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: python while loop if all conditions are equal then do another random choice from list

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Understanding the Problem: Selecting Unique Random Values in Python

When working in Python, you might find yourself needing to randomly select items from a list or set of values. A common problem arises when these randomly chosen values might be equal or identical, which can often feel cumbersome to handle. Take for example a scenario where you want to repeatedly choose three distinctive identifiers until all selected values are unique. At first glance, using loops may seem like a reasonable approach, but this can lead to unnecessary complexity and inefficiency in your code.

The Ineffective Approach: Using a While Loop

Here’s how your initial code might look when attempting this with a while loop, which checks if all three selected identifiers are equal:

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

In this approach, you continually check if the three selected identifiers are identical, only generating new choices when they are. This can lead to inefficiencies, especially if the odds of pulling the same value remain high.

The Effective Solution: Using Random Shuffle

A more elegant and efficient way to select unique random values in Python is by using the random.shuffle function. This technique eliminates the need for multiple checks and loops, saving you time and resources.

Step-by-Step Breakdown

Import Required Libraries:
To start with, you need to import the random module which contains functions that can help in randomizing items.

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

Create the List of Numbers:
Formulate a list of numbers from which you will later select your identifiers.

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

Shuffle the List:
By using the shuffle function, you can randomize the order of your list elements.

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

Select Unique Identifiers:
Finally, grab the first three identifiers from this shuffled list, ensuring all three values are unique:

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

This method is concise and significantly reduces the complexity of handling potential equality in randomly selected values.

Benefits of This Approach

Efficiency: The method avoids the overhead of multiple checks and loops, making your code run faster.

Simplicity: It streamlines the logic, making your code easier to read and maintain.

Uniqueness Guaranteed: By shuffling and selecting from a list, it inherently guarantees that selected items will not be the same.

Conclusion: Streamlining Your Random Selections

Instead of relying on while loops to filter out duplicate values, employing a single shuffle operation is a clear winning approach in Python. It not only solves the problem of ensuring unique selections but does so in an efficient and user-friendly manner. The next time you're faced with a similar task, consider leveraging the power of the random module for cleaner and faster code.