Enhance PSO File Documentation and Understanding

[Haleshot]

Description:
The PSO (Particle Swarm Optimization) file in the project's codebase contains essential functionality for optimizing neural network weights using the PSO algorithm. However, the documentation and understanding of the code can be improved to enhance clarity and facilitate better utilization.

Proposed Changes:

1. Add Detailed Function Documentation: The Particle class and its associated methods need comprehensive documentation to explain their purpose, inputs, and outputs. This includes functions such as __init__, frac_class_wt, forward, calc_fitness, and kmeans_eval. Providing detailed explanations and examples will help users understand how to interact with these functions effectively.

2. Clarify Variable Initialization: Comment lines explaining the initialization of weights and biases in the Particle class will enhance understanding, particularly regarding the range of initial weights and the rationale behind them.

3. Explain Fitness Calculation: The calc_fitness method requires detailed documentation to clarify how fitness values are calculated based on similarity measures and class weights. This includes explanations of concepts such as similarity matrix computation, nearest neighbors retrieval, and fitness evaluation using equation 6 from the referenced paper.

4. Document K-means Evaluation: The kmeans_eval method should be documented to explain its role in evaluating fitness using K-means clustering. Users would benefit from understanding how this evaluation method differs from the standard fitness calculation.

5. Include Vel Class Documentation: Similarly, the Vel class needs proper documentation to explain its purpose and functionality within the PSO algorithm. This includes descriptions of its attributes and any methods it contains.

Expected Outcome:

• Improved understanding of the PSO algorithm's implementation within the codebase.
• Enhanced clarity on how to interact with the Particle and Vel classes and their methods.
• Facilitated utilization of the PSO functionality for optimizing neural network weights.

Additional Context:
Enhancing the documentation of the PSO file aligns with the project's goal of promoting code readability and usability. Clear and comprehensive documentation fosters better collaboration and encourages contributions from the community.

Note: This issue aims to enhance the documentation and understanding of the PSO file. It does not involve modifying the actual functionality of the code but focuses on improving user comprehension and interaction with existing code.