python拆分和反向文本文件

I have a text file which stores data like name : score e.g.:

我有一个文本文件存储数据,如名称:分数例如:

bob : 10
fred : 3
george : 5

鲍勃:10弗雷德:3乔治:5

However, I want to make it so it says

但是,我想这样说

10 : bob
3 : fred
5 : george

10:鲍勃3:弗雷德5:乔治

What would the code be to flip it like that? Would I need to separate them first by removing the colon as I have managed this through this code?

那些代码会像那样翻转它?我是否需要首先删除冒号,因为我通过此代码管理了这个?

file = open("Class 3.txt", "r")
t4 = (file.read())
test =''.join(t4.split(':')[0:10])
print (test)

How would I finish it and make it say the reverse?

我怎么完成它并让它反过来说?

3 个解决方案

#1

This code handles fractional scores (e.g. 9.5), and doesn't care whether there are extra spaces around the : delimiter. It should be much easier to maintain than your current code.

此代码处理小数分数(例如9.5),并不关心:分隔符周围是否有额外的空格。它应该比您当前的代码更容易维护。

Class 3.txt:

bob : 10
fred : 3
george : 5

Code:

class_num = input('Which class (1, 2, or 3)? ')
score_sort = input('Sort by name or score? ').lower().startswith('s')

with open("Class " + class_num + ".txt", "r") as f:
    scores = {name.strip():float(score) for
              name,score in (line.strip().split(':') for line in f)}
    if score_sort:
        for name in sorted(scores, key=scores.get, reverse=True):
            print(scores.get(name), ':', name)
    else:
        for name in sorted(scores):
            print(name, ':', scores.get(name))

Input:

3
scores

Output:

10.0 : bob
5.0 : george
3.0 : fred

Input:

3
name

Output:

bob : 10.0
fred : 3.0
george : 5.0

#2

First, this is going to be a lot harder to do whole-file-at-once than line-at-a-time.

首先,一次整个文件要比一次一行完成要困难得多。

But, either way, you obviously can't just split(':') and then ''.join(…). All that's going to do is replace colons with nothing. You obviously need ':'.join(…) to put the colons back in.

但是,无论哪种方式,你显然不能只拆分(':')然后''。join(...)。所有这一切都是用冒险替换冒号。你显然需要':'。join(...)把冒号放回去。

And meanwhile, you have to swap the values around on each side of each colon.

同时,你必须在每个冒号的每一侧交换值。

So, here's a function that takes just one line, and swaps the sides:

所以,这是一个只占一行的函数,并交换边:

def swap_sides(line):
    left, right = line.split(':')
    return ':'.join((right, left))

But you'll notice there's a few problems here. The left has a space before the colon; the right has a space after the colon, and a newline at the end. How are you going to deal with that?

但是你会注意到这里有一些问题。左边有一个结肠前的空间;右边在冒号后面有一个空格,在结尾处有一个换行符。你打算如何应对?

The simplest way is to just strip out all the whitespace on both sides, then add back in the whitespace you want:

最简单的方法是去掉两边的所有空格,然后在你想要的空白处添加:

def swap_sides(line):
    left, right = line.split(':')
    return ':'.join((right.strip() + ' ', ' ' + left.strip())) + '\n'

But a smarter idea is to treat the space around the colon as part of the delimiter. (The newline, you'll still need to handle manually.)

但更聪明的想法是将结肠周围的空间视为分隔符的一部分。 (换行符,您仍然需要手动处理。)

def swap_sides(line):
    left, right = line.strip().split(' : ')
    return ' : '.join((right.strip(), left.strip())) + '\n'

But if you think about it, do you really need to add the newline back on? If you're just going to pass it to print, the answer is obviously no. So:

但是如果你考虑一下,你真的需要重新添加换行符吗?如果您打算将其传递给打印,答案显然是否定的。所以:

def swap_sides(line):
    left, right = line.strip().split(' : ')
    return ' : '.join((right.strip(), left.strip()))

Anyway, once you're happy with this function, you just write a loop that calls it once for each line. For example:

无论如何,一旦你对这个函数感到满意,你只需编写一个循环,为每一行调用一次。例如:

with open("Class 3.txt", "r") as file:
    for line in file:
        swapped_line = swap_sides(line)
        print(swapped_line)

#3

Let's learn how to reverse a single line:

让我们学习如何反转一行:

line = `bob : 10`
line.partition(' : ')  # ('10', ' : ', 'bob')
''.join(reversed(line.partition(' : '))  # 'bob : 10'

Now, combine with reading lines from a file:

现在,结合文件中的读取行:

for line in open('Class 3.txt').read().splitlines():
    print ''.join(reversed(line.partition(' : '))

Update

I am re-writing the code to read the file, line by line:

我正在重写代码来逐行读取文件:

with open('Class 3.txt') as input_file:
    for line in input_file:
        line = line.strip()
        print ''.join(reversed(line.partition(' : ')))