Question

我想用python读取文件结果必须像（元组列表）：

myList=[(1, 'assignment_1', 85,100', '0.05'),
        ('2', 'assignment_2', '80', '100', '0.05'),
        ('3', 'assignment_3', '95', '100', '0.05')]

该文件包含：

1 assignment_1 85 100 0.05
2 assignment_2 80 100 0.05
3 assignment_3 95 100 0.05

我的代码：

inputfile=open(filename,"r")
myList=[]
for line in inputfile.readlines():
    tuples=line.split()
    myList.append(tuples)
print(myList)
fileinput.close()

结果

[['1', 'assignment_1', '85', '100', '0.05'],
 ['2', 'assignment_2', '80', '100', '0.05'], 
 ['3', 'assignment_3', '95', '100', '0.05']]

如何将项目转换为每种类型（int，float）。我得到了一个列表列表，而不是元组列表

Answer 1

您可以在读取它们之后立即将元素转换为正确的类型：

from pprint import pprint

types = int, str, int, int, float
filename = 'assignments.txt'

with open(filename, "r") as inputfile:
    myList = []
    for line in inputfile:
        elements = tuple(t(e) for t,e in zip(types, line.split()))
        myList.append(elements)

pprint(myList)

输出：

[(1, 'assignment_1', 85, 100, 0.05),
 (2, 'assignment_2', 80, 100, 0.05),
 (3, 'assignment_3', 95, 100, 0.05)]

使用list comprehension：

可以更简洁地完成此操作

with open(filename, "r") as inputfile:
    myList = [tuple(t(e) for t,e in zip(types, line.split()))
                for line in inputfile]

另请注意，您不需要使用readlines()一次将file的所有行读入内存，因为文件可以逐行进行迭代。这在Python的在线文档中的Tutorial中有所描述。

Answer 2

添加到wpercy的答案，我认为实现这一目标的最简单方法如下：

with open(filename, 'r') as input_file:
    my_list = [tuple(line.split()) for line in input_file]

Answer 3

您可以使用以下内容：

myList = []
with open("text_to_tuple.txt") as f:
    for line in f:
        myList.append(tuple(line.rstrip().split())) # rstrip() removes line breaks
print(myList)    
# [('1', 'assignment_1', '85', '100', '0.05'), ('2', 'assignment_2', '80', '100', '0.05'), ('3', 'assignment_3', '95', '100', '0.05')]

将文件作为元组列表

3 个答案: