Question

我无法将2d列表转换为2d字典。在此之前我没有使用过2d词典，所以请耐心等待。我只是想知道为什么这会持续引发KeyError。在这个快速示例中，我希望字典看起来像{gender：{name：[food，color，number]}}

    2dList = [['male','josh','chicken','purple','10'],
             ['female','Jenny','steak','blue','11']]
    dict = {}
    for i in range(len(2dList)):
        dict[2dList[i][0]][2dList[i][1]] = [2dList[i][2], 2dList[i][3], 2dList[i][4]]

我不断收到错误消息： KeyError：'male'。我知道这是你为1d字典添加密钥的方法，但我不确定2d字典。我一直相信它是：

    dictionary_name[key1][key2] = value

Answer 1

您正在尝试构建嵌套字典。但是没有明确初始化第二层词典。每次都需要执行此操作，遇到新密钥。顺便说一句，2dlist是一种在python中声明变量的错误方法。这应该适合你：

dList = [['male','josh','chicken','purple','10'],
         ['female','Jenny','steak','blue','11']]
dict = {}
for i in range(len(dList)):
    if not dList[i][0] in dict.keys():
        dict[dList[i][0]] = {}
    dict[dList[i][0]][dList[i][1]] = [dList[i][2], dList[i][3], dList[i][4]]
print(dict)

Answer 2

要获得更多或更少的“理智”结果，请使用以下（字典列表，每个字典的格式为{gender: { name: [food, color, number] }}）：

l = [['male','josh','chicken','purple','10'], ['female','Jenny','steak','blue','11']]
result = [{i[0]: {i[1]:i[2:]}} for i in l]
print(result)

输出：

[{'male': {'josh': ['chicken', 'purple', '10']}}, {'female': {'Jenny': ['steak', 'blue', '11']}}]

Answer 3

你可以尝试这个:)如果你的male

中有多个female或List，它也会有效

List = [['male','josh','chicken','purple','10'],
        ['female','Jenny','steak','blue','11']]


d = {}

for l in List:
    gender = l[0]
    name = l[1]
    food = l[2]
    color = l[3]
    number = l[4]

    if gender in d: # if it exists just add new name by creating new key for name
        d[gender][name] = [food,color,number]
    else: # create new key for gender (male/female)
        d[gender] = {name:[food,color,number]}

Answer 4

您收到KeyError，因为您尝试以male作为关键字访问字典中的不存在条目

您可以使用defaultdict代替dict。

from collections import defaultdict

2dList = [['male','josh','chicken','purple','10'],
             ['female','Jenny','steak','blue','11']]

dict = defaultdict(list)
for i in range(len(2dList)):
    dict[2dList[i][0]][2dList[i][1]] = [2dList[i][2], 2dList[i][3], 2dList[i][4]]

Answer 5

试试这个

twodList = [['male','josh','chicken','purple','10'],
             ['female','Jenny','steak','blue','11']]
dic = {twodList[i][0]: {twodList[i][1]: twodList[i][2:]} for i in range(len(twodList))}

正如评论中提到的那样，你不能有一个以数字开头的变量。

Answer 6

list1=[['male','josh','chicken','purple','10'],['female','Jenny','steak','blue','11'],['male','johnson','chicken','purple','10'],['female','jenniffer','steak','blue','11']]
dict = {}
for i in range(len(list1)):
    if list1[i][0] in dict:
        if list1[i][1] in dict[list1[i][0]]:
            dict[list1[i][0]][list1[i][1]] = [list1[i][2], list1[i][3], list1[i][4]]
        else:
            dict[list1[i][0]][list1[i][1]] = {}
            dict[list1[i][0]][list1[i][1]] = [list1[i][2], list1[i][3], list1[i][4]]
    else:
        dict[list1[i][0]] = {}
        if list1[i][1] in dict[list1[i][0]]:
            dict[list1[i][0]][list1[i][1]] = [list1[i][2], list1[i][3], list1[i][4]]
        else:
            dict[list1[i][0]][list1[i][1]] = {}
            dict[list1[i][0]][list1[i][1]] = [list1[i][2], list1[i][3], list1[i][4]]
print dict

上面给出了以下输出： {＆＃34;男性＆＃34; {＆＃34;约什＆＃34;：[＆＃34;鸡＆＃34;＆＃34;紫＆＃34;＆＃34; 10＆＃34]，＆＃34;约翰逊＆＃34;：[＆＃34;鸡＆＃34;＆＃34;紫＆＃34;＆＃34; 10＆＃34;]}＆＃34;女性＆＃34; {＆＃ 34; jenniffer＆＃34;：[＆＃34;牛排＆＃34;＆＃34;蓝色＆＃34;＆＃34; 11＆＃34]，＆＃34;珍妮＆＃34;：[＆＃34;牛排＆＃34;＆＃34;蓝色＆＃34;＆＃34; 11＆＃34;]}}

使用for循环将列表转换为2d字典

6 个答案: