迪杰斯特拉 - 最近邻确定

Question

我在使用Dijkstra算法找最近邻居的时候遇到了麻烦，结果有点奇怪。首先，这是我的网络文件内容，表示7个节点之间的距离：

（第一列的数字1到7不算在内）

接下来是我的代码：

> infinity = 1000000 invalid_node = -1
> startNode = 0
> 
> #Values to assign to each node class Node:
>      distFromSource = infinity
>      previous = invalid_node
>      visited = False
> 
> #read in all network nodes
> #node = the distance values between nodes def network():
>     f = open ('network.txt', 'r')
>     theNetwork = [[int(node) for node in line.split(',')] for line in
> f.readlines()]
>     #print theNetwork
> 
>     return theNetwork
> 
> #for each node assign default values
> #populate table with default values def populateNodeTable():
>     nodeTable = []
>     index = 0
>     f = open('network.txt', 'r')
>     for line in f:
>       node = map(int, line.split(','))
>       nodeTable.append(Node())
>      
>       #print "The previous node is " ,nodeTable[index].previous
>       #print "The distance from source is " ,nodeTable[index].distFromSource
>       index +=1
>     nodeTable[startNode].distFromSource =
> 0
> 
>     return nodeTable
> 
> #find the nearest neighbour to a particular node def
> nearestNeighbour(nodeTable,
> theNetwork):
>      nearestNeighbour = []
>      nodeIndex = 0
>      for node in nodeTable:
>           if node != 0 and Node.visited == False:
>              nearestNeighbour.append(nodeIndex)
>              nodeIndex +=1
>      print nearestNeighbour
> 
>      return nearestNeighbour
> 
> def tentativeDistance (theNetwork,
> nodeTable, nearestNeighbour):
>     shortestPath = []
>     for nodeIndex in nearestNeighbour:
>          currentDistance = nearestNeighbour[] + startNode
>          print currentDistance
> ##         if currentDistance < Node.distFromSource:
> ##            theNetwork[Node].previous = nodeIndex
> ##            theNetwork[Node].length = nodeIndex
> ##            theNetwork[Node].visited = True;
> ##            shortestPath.append(indexNode)
> ##            nodeIndex +=1
> ##    print shortestPath
> 
> currentNode = startNode
> 
> if __name__ == "__main__":
>     nodeTable = populateNodeTable()
>     theNetwork = network()
>     nearestNeighbour(nodeTable, theNetwork)
>     tentativeDistance(theNetwork, nodeTable, nearestNeighbour)

我想查看网络函数提供的值，在populateNodeTable函数中把所有节点的'visited'状态设为'false'，然后通过查看之前函数提供的值来确定节点的最近邻居，但我收到了这个错误信息：

> Traceback (most recent call last):  
> File "C:\Documents and Settings\Harvey\Desktop\2dArray.py", line 77, in <module>
>     tentativeDistance(theNetwork, nodeTable, nearestNeighbour)   File
> "C:\Documents and Settings\Harvey\Desktop\2dArray.py", line 51, in tentativeDistance
>     for nodeIndex in nearestNeighbour: TypeError: 'function' object is not iterable

当我只运行我的网络函数时，得到的输出是：

[[0, 2, 4, 1, 6, 0, 0], [2, 0, 0, 0, 5, 0, 0], [4, 0, 0, 0, 5, 5, 0], [1, 0, 0, 0, 1, 1, 0], [6, 5, 0, 1, 0, 5, 5], [0, 0, 5, 1, 5, 0, 0], [0, 0, 0, 0, 5, 0, 0]]

到目前为止，一切正常 - 当我同时运行populateNodeTable函数和网络函数时，得到的输出是：

> The previous node is  -1 
  The distance from source is  1000000 # happens 7 times#
>

这也很好 - 在执行nearestNeighbour函数后，我的输出是：

[0, 1, 2, 3, 4, 5, 6]

这个输出是错误的，这就是我问题的开始。

另外，当我运行所有代码，包括tentativeDistance时，我得到了这个错误：

> for nodeIndex in nearestNeighbour:
  TypeError: 'function' object is not iterable

抱歉这篇帖子有点长，我只是对无法掌握看起来很基础的功能感到沮丧。

错误调试状态管理距离计算图算法节点遍历最近邻迪杰斯特拉算法网络函数

迪杰斯特拉 - 最近邻确定

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