Question

我是Python新手，目前我有一个哈希表类，通过线性探测解决冲突。但是，如果负载系数高于2/3，我想将数组的大小加倍。但是，我一直收到错误

if self.array[i]!=None:
IndexError: invalid index

是因为每次更改表格大小时，我的getLoadandAverageProbeLength都不会更新尺寸吗？

我的设定项目功能：

 def __setitem__(self, key, value):
    position = self.hash_value(key)
    sameKeyCollision=False
    load,averageProbeLength= self.getLoadAndAverageProbeLength(self.totalProbeLength)
    loadFactor=load
    if loadFactor<(2/3):
        if self.array[position] is None:#found empty slot, collision resolve
            self.array[position] = (key, value)
            self.count += 1
            sameKeyCollision=False


            return
        elif self.array[position][0] == key:#found key
            self.array[position] = (key, value)#update value, no collision
            return
        elif self.array[position][0] !=key and sameKeyCollision==False:#not found try next,first time collision
            position = (position+1) % self.table_size
            self.totalProbeLength+=1
            self.collision+=1
            sameKeyCollision=True
        elif self.array[position][0] !=key and sameKeyCollision==True:#probing
            position = (position+1) % self.table_size
            self.totalProbeLength+=1

我的getLoadAndAverageProbeLength

def getLoadAndAverageProbeLength(self,probeLength):
    count=0
    averageProbeLength=0
    for i in range(self.table_size):
        if self.array[i]!=None:
            count+=1

    load= count/self.table_size

    if count!=0:
        averageProbeLength=probeLength/count
    return load,averageProbeLength

这是我的哈希表的类构造函数：

def __init__(self, size=2):
    self.count = 0
    self.table_size = size
    self.array = build_array(self.table_size)
    self.collision=0
    self.totalProbeLength=0

这是我的追溯：

   Traceback (most recent call last):
  File "C:\Users\User\Desktop\Assignment3Task3(b).py", line 18, in <module>
main()
 File "C:\Users\User\Desktop\Assignment3Task3(b).py", line 15, in main
readFile(filename)
 File "C:\Users\User\Desktop\Assignment3Task3(b).py", line 10, in readFile
hashTable[line]=line
 File "C:\Users\User\Desktop\Assignment3Task4.py", line 55, in __setitem__
self.__setitem__(key,value)
 File "C:\Users\User\Desktop\Assignment3Task4.py", line 29, in __setitem__
load,averageProbeLength= self.getLoadAndAverageProbeLength(self.totalProbeLength)
File "C:\Users\User\Desktop\Assignment3Task4.py", line 83, in getLoadAndAverageProbeLength
if self.array[i]!=None:

IndexError：索引无效

如何在Python的哈希表中实现动态哈希？

0 个答案: