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我對Dijkstra算法中對最近鄰居的確定感到失落。我得到了奇怪的結果如下 首先，這是我的網絡文件的內容，代表7個節點之間的距離：Dijkstra - 最近鄰點確定
（第一列1-7的數字不包括在內）
現在對於我的代碼：
> 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)
所以，我想看看通過網絡功能提供的值，將所有節點「訪問=假」在populateNodeTable功能，然後通過查看以前的功能提供的值決定了節點的近鄰，但我得到這個錯誤信息：
> 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
當我剛剛運行我的網絡功能，我得到這個輸出中：
[[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]]
到目前爲止，一切都很好 - 當我和我的網絡功能一起經營我populateNodeTable功能我得到這樣的輸出：
> The previous node is -1
The distance from source is 1000000 # happens 7 times#
>
而且，這是很好的 - 我的執行功能nearestNeighbour後，我的輸出中除了上述功能是：
[0, 1, 2, 3, 4, 5, 6]
這個輸出是錯誤的，是我的問題開始
此外，當我跑我的所有代碼，包括tentativeDistance我得到這個錯誤：
> for nodeIndex in nearestNeighbour:
TypeError: 'function' object is not iterable
我很抱歉這篇文章長時間囉嗦，我只是沮喪，我不能掌握什麼似乎是基本功能