如何将CSV数据存储在具有字典和列表的嵌套字典中?

时间:2014-07-26 03:37:01

标签: python list python-2.7 csv dictionary

我有以下CSV数据,

Rule1,Status1,1
Rule1,Status2,1
Rule1,Status3,1
Rule1,Status4,2
Rule2,Status1,2
Rule2,Status2,1
Rule2,Status3,1
Rule2,Status4,3

我有一个名为Rules的列表中存储的唯一规则(第一列)。我希望我的字典看起来如下:

DictionaryFull = {
                  'Rule1' : {1 : [Status1, Status2, Status3], 2 : [Status4]},
                  'Rule2' : {1 : [Status2, Status3], 2 : [Status1], 3 : [Status4]}
                 }

以下是我的尝试:

openfile = ('data.csv', 'rU')
finalfile = csv.reader(openfile, delimiter=',')

FullDictionary = {}

for row in finalfile:
  for j in range (0, 300): #300 number of rules 
    if Rules[j] not in FullDictionary:
        for i in range(1, 71): #These are third column numbers 1 - 71 
            if i == int(row[2]) and row[0] == Rules[j]:
                FullDictionary = {Rules[j] : { i : [].append[row[1]}}
                    print FullDictionary

但我得到以下结果:

{'Rule1': {1 : None}} and so on

我做错了吗?如何完成这个包含另一个字典和列表的字典的任务。

我试过了:

def something():
    full_dictionary = {}
    with open(DataFilePath) as f:
        reader = csv.reader(f)
        for row in reader:
            rule = row[2], status = row[0], num = int(row[5])
            r = full_dictionary.setdefault(rule, {})
            r.setdefault(num, []).append(status)

    print full_dictionary

错误:ValueError:关闭文件上的I / O操作

2 个答案:

答案 0 :(得分:2)

关于使用collection.defaultdict

import csv
from collections import defaultdict

full_dictionary = defaultdict(lambda: defaultdict(list))
with open('data.csv') as f:
    reader = csv.reader(f)
    for rule, status, num in reader:
        full_dictionary[rule][num].append(status)

print full_dictionary

输出:

defaultdict(<function <lambda> at 0x00000000025A6438>, {
    'Rule2': defaultdict(<type 'list'>, {
        '1': ['Status2', 'Status3'],
        '3': ['Status4'],
        '2': ['Status1']
     }),
     'Rule1': defaultdict(<type 'list'>, {
         '1': ['Status1', 'Status2', 'Status3'],
         '2': ['Status4']
     })
})

如果您不想使用defaultdict,则必须关注新密钥。

例如,使用dict.setdefault

import csv

full_dictionary = {}
with open('data.csv') as f:
    reader = csv.reader(f)
    for rule, status, num in reader:
        r = full_dictionary.setdefault(rule, {})
        r.setdefault(num, []).append(status)

print full_dictionary

输出:

{'Rule1': {'1': ['Status1', 'Status2', 'Status3'], '2': ['Status4']},
 'Rule2': {'1': ['Status2', 'Status3'], '2': ['Status1'], '3': ['Status4']}}

答案 1 :(得分:0)

list.append返回无,因此您的作业Rules[j] = [].append([row[1])正在设置Rules[j] = None

修改为:

FullDictionary = {Rules[j] : { i : [row[1]}}

old_value = Rules[j].get(i, [])
old_value.append(row[1])

取决于您希望实现的目标。