Add New Preferential Attachment Example

[Spartan-71]

Summary

This PR introduces a new Preferential Attachment simulation example, inspired by the Barabási–Albert model of network growth. The simulation models how a network evolves over time as new nodes are added and preferentially attach to existing nodes with higher degrees, leading to the emergence of scale-free network structures.

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Features

• Node Agents: Represent individual nodes in the network.
• Preferential Attachment Rule: New nodes attach to existing nodes with probability proportional to node degree.
• Data Collection: Tracks the number of nodes with degree 1 over time.
• Dynamic network topology: Dynamic graph representation of the growing network.

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Implementation Details

• Uses Mesa’s Network grid to embed and manage the graph.
• Relies on networkx for graph data structure and operations.
• Probabilities for attachment are derived from current node degrees.
• Includes a DataCollector to track key metrics like node degrees.

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Visualization

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