如何回圈到字典中的字典以指定方式組織CSV中的資料

我被一個問題困擾了幾天。我做了一個腳本：

- 從 CSV 檔案中獲取資料 - 按資料檔案第一列中的相同值對其進行排序 - 在不同模板文本檔案的特定欄位行中插入排序的資料 - 將檔案保存在盡可能多的副本中，因為資料檔案中的第一列中有不同的值下圖顯示了它是如何作業的：

但是我還需要做兩件事。當在如上所示的單獨檔案中時，資料檔案的第二列中有一些相同的值，那么這個檔案應該從第三列插入值，而不是從第二列重復相同的值。在下面的圖片中，我展示了它的外觀：

我還需要通過“_”從資料檔案中添加第一列的某處分隔值。

有資料檔案：

111_0,3005,QWE
111_0,3006,SDE
111_0,3006,LFR
111_1,3005,QWE
111_1,5345,JTR
112_0,3103,JPP
112_0,3343,PDK
113_0,2137,TRE
113_0,2137,OMG

我做了代碼：

import shutil
 
with open("data.csv") as f:
    contents = f.read()
    contents = contents.splitlines()
 
values_per_baseline = dict()
 
for line in contents:
    key = line.split(',')[0]
    values = line.split(',')[1:]
    if key not in values_per_baseline:
        values_per_baseline[key] = []
    values_per_baseline[key].append(values)
 
for file in values_per_baseline.keys():
    x = 3
    shutil.copyfile("of.txt", (f"of_%s.txt" % file))
    filename = f"of_%s.txt" % file
    for values in values_per_baseline[file]:
        with open(filename, "r") as f:
            contents = f.readlines()
            contents.insert(x, '      o = '   values[0]   '\n          '   'a = '   values[1]  '\n')
        with open(filename, "w") as f:
            contents = "".join(contents)
            f.write(contents)
            f.close()

我一直在嘗試制作類似于串列字典的字典，但我無法以正確的方式實作它以使其正常作業。任何幫助或建議將不勝感激。

uj5u.com熱心網友回復：

當我運行您的代碼時，我收到此錯誤：

    contents.insert(x, '      o = '   values[0]   '\n          '   'a = '   values[3]  '\n')
IndexError: list index out of range

讓我們想想這個錯誤是從哪里來的。這是一個IndexError在名單上。這條線上使用的唯一串列values似乎是一個開始尋找的好地方。

要除錯，您可以考慮在吐出錯誤的行之前添加類似這樣的內容：

            print(values)
            print(values[0])
            print(values[3])

這使

['3005', 'QWE']
3005
Traceback (most recent call last):
  File "qqq.py", line 25, in <module>
    print(values[3])
IndexError: list index out of range

所以問題在于values[3]，這是有道理的，因為len(values)==2和 所以索引需要是0和1。如果我們更改values[3]為，values[1]那么我認為您會得到您想要的。例如：

$ cat of_111_0.txt
line
line
line
      o = 3006
          a = LFR
      o = 3006
          a = SDE
      o = 3005
          a = QWE
line
line
line
line
line

為了解決問題的下一步，我建議您將第一個回圈更改為：

for line in contents:
    key = line.split(',')[0]
    values = line.split(',')[1:]
    if key not in values_per_baseline:
        values_per_baseline[key] = {}
    if values[0] not in values_per_baseline[key]:
        values_per_baseline[key][values[0]] = values[1]
    else:
        values_per_baseline[key][values[0]]  = '<COMMA>'   values[1]

這使您的字典成為：

{'111_0': {'3005': 'QWE', 
           '3006': 'SDE<COMMA>LFR'}, 
 '111_1': {'3005': 'QWE', 
           '5345': 'JTR'}, 
 '112_0': {'3103': 'JPP', 
           '3343': 'PDK'}, 
 '113_0': {'2137': 'TRE<COMMA>OMG'}}

然后在寫入檔案時，您需要將回圈更改為：

        for key in values_per_baseline[file]:
            contents.insert(x, f'{6*sp}o = {key}\n{10*sp}a = {values_per_baseline[file][key]}\n')

你的檔案現在看起來像：

line
line
line
      o = 3006
          a = SDE<COMMA>LFR
      o = 3005
          a = QWE
line
line
line
line
line

你可以做的其他事情

現在，您可以采取一些措施來簡化代碼，同時保持其可讀性。*

• On lines 10 and 11, there is no need to use line.split twice. Just add a line that has something like split_line = line.split(',') and then have key = split_line[0] and values = split_line[1:]. (You could do away with key and values all together and just reference split_line[0] and split_line[1] but that would make your code less readable.
• On line 17, you are defining x in every loop. Just take it out of the loop.
• On lines 12 and 13, you are first using (f"of_%s.txt" % file) and then defining it in a file on the next line. Suggest you define filename first and then just have shutil.copyfile("of.txt", filename). Also, you are using f-strings incorrectly. You could just write filename = f"of_{file}.txt".
• On line 23, you could change your insert command to an f-string (if you find it more readable). For example: contents.insert(x, f'{6*sp}o = {values[0]}\n{10*sp}a = {values[1]}\n')
• At the end, in your for values in values_per_baseline.keys() loop, you are opening and closing files way more than you need to. You can reorder your operations:

    with open(filename, "r") as f:
        contents = f.readlines()
        for values in values_per_baseline[file]:
            contents.insert(x, '      o = '   values[0]   '\n          '   'a = '   values[1]  '\n')
    with open(filename, "w") as f:
        contents = "".join(contents)
        f.write(contents)
        f.close()

*For a short script like this, I would argue that making sure it is readable is more important than making sure it is efficient, since you will want to be able to come back in 3 weeks or 3 years and understand what you did. For that reason, I would also recommend you comment what you did.

標籤：Python 列表 CSV 字典 多列

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