Bellman-Ford 单源最短路径算法 Python实现

Bellman-Ford 单源最短路径算法 Python实现

若最短路径不只一条，可寻找到多条最短路径

完整代码：

import numpy as np
import pandas
import numpy
import os
import shutil


def bellmanford(filepath):
    # 读csv数据
    data_read = pandas.read_csv(filepath, dtype='int')

    # 生成列表
    data = data_read.values.tolist()

    # 遍历节点个数
    v_max = max(np.max(data, axis=0)[1], np.max(data, axis=0)[2])
    v = v_max + 1

    # 生成矩阵
    graph = numpy.array(data)

    # 定义邻接矩阵，初始值为无穷大
    D = numpy.zeros((v, v), dtype='float')
    for i in range(v):
        for j in range(v):
            D[i][j] = numpy.inf

    # 根据图G为邻接矩阵赋值
    for i in range(0, len(graph)):
        D[graph[i][1]][graph[i][2]] = graph[i][3]
    for i in range(v):
        D[i][i] = 0

    # 建立前置节点列表
    Pr = [[]for i in range(v)]

    # 建立路长列表, 并初始化原点到各点的路长
    u = numpy.zeros(v, dtype='float')
    for