feat: Implement Yen's Algorithm for K-Shortest Paths #625
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- Added Yen's Algorithm implementation to find the K shortest paths between two nodes in a graph. - Supports applications in network routing, transportation planning, and logistics. - Includes test cases to validate the correctness of the implementation. - Optimized for performance and usability within the graph algorithms module.
czgdp1807
reviewed
Mar 11, 2025
pydatastructs/graphs/algorithms.py
Outdated
| @@ -11,6 +11,8 @@ | |||
| from pydatastructs.graphs.graph import Graph | |||
| from pydatastructs.linear_data_structures.algorithms import merge_sort_parallel | |||
| from pydatastructs import PriorityQueue | |||
| from copy import deepcopy | |||
| import heapq | |||
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We do have heapq implemented in PyDataStructs? I think PriorityQueue and heapq are the same?
| from pydatastructs.utils.raises_util import raises | ||
| import pytest |
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We don't need to import this.
| for i, path in enumerate(k_shortest_paths): | ||
| assert path == expected_paths[i], f"Path {i} does not match expected path. Got {path}, expected {expected_paths[i]}" | ||
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| _test_yen_algorithm("List") |
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Why don't we support matrix representation of graphs?
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Why don't we support matrix representation of graphs?
The AdjacencyMatrix implementation does not support dynamic modifications like removing vertices or edges during runtime. Since Yen's algorithm requires modifying the graph (e.g., removing edges and vertices to find alternative paths), it cannot work with the AdjacencyMatrix implementation in its current form.
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✨ Feature: Yen's Algorithm for K-Shortest Paths
FIXES: #622
📌 Description
This PR introduces Yen's Algorithm, which finds the K shortest paths between a source and destination node in a graph. The algorithm efficiently computes multiple alternative paths, making it useful for applications such as:
🛠️ Changes