将一组文本文件中的第 2 列添加到 1 个文本文件

Question

我有一组文本文件，我希望将每个文本文件的第二列按顺序添加到一个新的文本文件中。这些文件是制表符分隔的，格式如下：

name dave
age 35
job teacher
income 30000

我已经生成了一个文件，其中一个文件的第一列代替了第二列，希望能简化问题：

0 name
0 age 
0 job
0 income 

我有大量这些文件，并希望将它们全部放在制表符分隔的文本文件中，例如：

name dave mike sue
age 35 28 40
job teacher postman solicitor
income 30000 20000 40000

我有一个文本文件，其中只包含名为 all_libs.txt 的所有文件的名称

到目前为止，我已经写了：

#make a sorted list of the file names
with open('all_libs.txt', 'r') as lib:
     people = list([line.rstrip() for line in lib])
     people_s = sorted(people)

i=0

while i< len(people_s):
    with open(people_s[i]) as inf:
        for line in inf:                
            parts = line.split() #split line into parts
            if len(parts) > 1:    #if more than 1 discrete unit in parts
                with open("all_data.txt", 'a') as out_file: #append column2 to all_data
                    out_file.write((parts[1])+"\n")

i=i+1 #go to the next file in the list

在打开每个新文件时，我想将其添加为新列，而不是仅作为新行追加。真的很感激任何帮助吗？我意识到像 SQL 这样的东西可能会让这变得简单，但我从未使用过它，也没有时间致力于 SQL 的学习曲线。非常感谢。

Answer 1

这是一种非常不切实际的数据存储方式——每条记录都分布在所有行中，因此在读取文件和（如您所见）添加记录时很难重建记录。

您应该使用标准格式，例如 csv 或（在这种情况下更好）json：

例如，您可以像这样将它们保存为 CSV：

name,age,job,income
dave,35,teacher,30000
mike,28,postman,20000
sue,40,solicitor,40000

阅读此文件：

>>> import csv
>>> with open("C:/Users/Tim/Desktop/people.csv", newline="") as infile:
...     reader = csv.DictReader(infile)
...     people = list(reader)

现在你有一个人员列表：

>>> people
[{'income': '30000', 'age': '35', 'name': 'dave', 'job': 'teacher'}, 
 {'income': '20000', 'age': '28', 'name': 'mike', 'job': 'postman'}, 
 {'income': '40000', 'age': '40', 'name': 'sue', 'job': 'solicitor'}]

您可以轻松访问：

>>> for item in people:
...     print("{0[name]} is a {0[job]}, earning {0[income]} per year".format(item))
...
dave is a teacher, earning 30000 per year
mike is a postman, earning 20000 per year
sue is a solicitor, earning 40000 per year

现在添加新记录只需将它们添加到文件末尾即可：

>>> with open("C:/Users/Tim/Desktop/people.csv", "a", newline="") as outfile:
...    writer = csv.DictWriter(outfile,
...                            fieldnames=["name","age","job","income"])
...    writer.writerow({"name": "paul", "job": "musician", "income": 123456,
...                     "age": 70})

结果：

name,age,job,income
dave,35,teacher,30000
mike,28,postman,20000
sue,40,solicitor,40000
paul,70,musician,123456

或者您可以将其保存为 JSON：

>>> import json
>>> with open("C:/Users/Tim/Desktop/people.json", "w") as outfile:
...     json.dump(people, outfile, indent=1)

结果：

[
 {
  "income": "30000", 
  "age": "35", 
  "name": "dave", 
  "job": "teacher"
 }, 
 {
  "income": "20000", 
  "age": "28", 
  "name": "mike", 
  "job": "postman"
 }, 
 {
  "income": "40000", 
  "age": "40", 
  "name": "sue", 
  "job": "solicitor"
 }
]

Answer 2

file_1 = """
name dave1
age 351
job teacher1
income 300001"""

file_2 = """
name dave2
age 352
job teacher2
income 300002"""

file_3 = """
name dave3
age 353
job teacher3
income 300003"""

template = """
0 name
0 age
0 job
0 income"""

假设上面是从文件中读取的

_dict = {}


def concat():
    for cols in template.splitlines():
        if cols:
            _, col_name = cols.split()
            _dict[col_name] = []

    for each_file in [file_1, file_2, file_3]:
        data = each_file.splitlines()
        for line in data:
            if line:
                words = line.split()
                _dict[words[0]].append(words[1])

    _text = ""

    for key in _dict:
        _text += '\t'.join([key, '\t'.join(_dict[key]), '\n'])

    return _text

print concat()

输出

job teacher1    teacher2    teacher3    
age 351 352 353 
name    dave1   dave2   dave3   
income  300001  300002  300003