Minor Performance Improvements in BitArray and Luhn Algorithm

[michaelkrisper]

This pull request introduces several improvements and refactorings across the Algorithms and DataStructures namespaces. The main focus is on code simplification, performance optimization, and improved clarity, especially in the BitArray and SoundexEncoder classes, as well as minor documentation and logic updates in the Luhn algorithm and vector extensions.

Data structure and algorithm optimizations

• Refactored multiple methods in BitArray to use StringBuilder for string manipulations and replaced manual string concatenation with more efficient approaches, improving performance and readability. This affects logical operations and compile methods. [1] [2] [3] [4] [5] [6] [7] [8] [9]
• Simplified the BitArray constructor to initialize the internal array in a single line, handling invalid sizes more cleanly.

Algorithm logic and clarity improvements

• Improved the Luhn algorithm implementation in Luhn.cs by clarifying variable names, updating comments, and refining the logic for finding a missing digit. Also updated documentation for better clarity.
• Fixed a typo in the documentation for the ThrowIfSequenceIsInvalid method in BitArray.cs.

Encoder codebase simplification

• Moved the character mapping dictionary in SoundexEncoder from a local variable to a static readonly field, reducing repeated allocations and improving performance. Updated the mapping logic to use this field. [1] [2]
• Added missing using directives to NysiisEncoder.cs for consistency and potential future usage.

Utility improvements

• Simplified the Magnitude method in VectorExtensions.cs to a single return statement, improving readability.

• I have performed a self-review of my code
• My code follows the style guidelines of this project
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Comments in areas I changed are up to date
• I have added comments to hard-to-understand areas of my code
• I have made corresponding changes to the README.md

[Copilot]

Pull Request Overview

This pull request introduces performance optimizations and code improvements across multiple classes, primarily focusing on replacing string concatenation with StringBuilder for better performance and simplifying code logic. The changes target the BitArray data structure operations, Luhn algorithm clarity, and encoder performance.

• String concatenation replaced with StringBuilder in BitArray operations for better performance
• Luhn algorithm variable names and documentation improved for clarity
• SoundexEncoder character mapping moved to static field to reduce allocations
• Minor code simplifications in VectorExtensions and constructor logic

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
Utilities/Extensions/VectorExtensions.cs	Simplified Magnitude method to single return statement
DataStructures/BitArray.cs	Replaced string concatenation with StringBuilder, simplified constructor, fixed typo
Algorithms/Other/Luhn.cs	Improved variable names and documentation for clarity
Algorithms/Encoders/SoundexEncoder.cs	Moved character mapping to static readonly field for performance
Algorithms/Encoders/NysiisEncoder.cs	Added using directives for consistency

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[codecov]

Codecov Report

❌ Patch coverage is 97.18310% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 95.20%. Comparing base (f1fde96) to head (4b3da4a).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
Algorithms/Other/Luhn.cs	92.30%	0 Missing and 1 partial ⚠️
DataStructures/BitArray.cs	96.29%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #528   +/-   ##
=======================================
  Coverage   95.19%   95.20%           
=======================================
  Files         272      272           
  Lines       10920    10875   -45     
  Branches     1536     1529    -7     
=======================================
- Hits        10395    10353   -42     
+ Misses        400      397    -3     
  Partials      125      125           

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[Copilot]

Pull Request Overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

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[siriak]

Looks good, thanks!