KruskalHamiltonPrimal 0.0.2

Библиотека для работы с графами и алгоритмами, включая алгоритмы Крускала, Гамильтона и минимального остовного дерева

Minimal Spanning Tree and Hamiltonian Cycle

This project implements algorithms for finding the minimum spanning tree (MST) and the Hamiltonian cycle in graphs. It includes three main classes: Kruskal', HamiltonandPrimal_min', each of which provides different methods for working with graphs.

Installation

To work with the project, you need to install the following libraries:

pip install networkx matplotlib

Description of classes

1. Kruskal

The `Kruskal' class implements the Kruskal algorithm for finding the minimum spanning tree.

Constructor

Kruskal(points, edges)

• points: A list of coordinates of graph vertices.
• edges: A list of graph edges, where each edge is represented as a tuple (u, v, weight).

Methods

• draw_only(k): Displays the graph and its edges.
• `view(min_edges, max_edges, k)': Displays a graph with a minimum and maximum spanning tree.
• kruskals_algorithm(edges): Implements the Kraskal algorithm for finding MST.
• `sort_edges_min()': Sorts the edges in ascending order of weight.
• `sort_edges_max()': Sorts the edges in descending order of weight.
• result_weight(edges): Calculates and outputs the total weight of the tree.

2. Hamilton

The `Hamilton' class implements an algorithm for finding a Hamiltonian cycle.

Constructor

Hamilton(points, edges)

• points: A list of coordinates of graph vertices.
• edges: A list of graph edges in the form of pairs of vertex indexes.

Methods

• cycle_exist(cycle): Checks for a Hamiltonian cycle and outputs it.
• `draw()': Visualizes the graph.
• `avoidable()': Outputs the available vertices.
• `hamiltonian_cycle(start)': Finds a Hamiltonian cycle starting from a given vertex.
• draw_graph(path=None): Displays a graph with a highlighted Hamiltonian cycle.

3. Primal_min

The `Primal_min' class implements the Prim algorithm for finding the minimum spanning tree.

Constructor

Primal_min(graph)

• `graph': A graph in the form of a dictionary, where the keys are vertices and the values are lists of edges with weights.

Methods

• run(begin): Starts the Prim algorithm, starting from the specified vertex.
• `min_tree()': Outputs the minimum spanning tree and its total weight.

Usage example

# Example of creating a graph and finding a minimum spanning tree
points = [(0, 0), (1, 1), (2, 0), (1, -1)]
edges = [(0, 1, 1.5), (0, 2, 1.0), (1, 3, 2.0), (2, 3, 1.0)]

kruskal = Kruskal(points, edges)
sorted_edges = kruskal.sort_edges_min()
mst = kruskal.alg_Kraskala(sorted_edges)
kruskal.view(mst, sorted_edges, 3)

# An example of finding a Hamiltonian cycle
hamilton = Hamilton(points, edges)
cycle = hamilton.hamiltonian_cycle(0)
hamilton.cycle_exist(cycle)
hamilton.draw_graph(cycle)

License

This project is licensed under the MIT License. Please review the LICENSE file for more information. ``