Python:如何遍历行块 [英] Python: How to loop through blocks of lines

问题描述

如何遍历由空行分隔的行块?该文件如下所示:

How to go through blocks of lines separated by an empty line? The file looks like the following:

ID: 1
Name: X
FamilyN: Y
Age: 20

ID: 2
Name: H
FamilyN: F
Age: 23

ID: 3
Name: S
FamilyN: Y
Age: 13

ID: 4
Name: M
FamilyN: Z
Age: 25

我想遍历块并获取 3 列列表中的字段名称、姓氏和年龄:

I want to loop through the blocks and grab the fields Name, Family name and Age in a list of 3 columns:

Y X 20
F H 23
Y S 13
Z M 25

推荐答案

这是另一种方式，使用 itertools.groupby.函数groupy 遍历文件的各行并为每个line 调用isa_group_separator(line).isa_group_separator 返回 True 或 False(称为 key)，然后 itertools.groupby 然后将产生相同 True 或 False 的所有连续行分组结果.

Here's another way, using itertools.groupby. The function groupy iterates through lines of the file and calls isa_group_separator(line) for each line. isa_group_separator returns either True or False (called the key), and itertools.groupby then groups all the consecutive lines that yielded the same True or False result.

这是将行收集到组中的一种非常方便的方法.

This is a very convenient way to collect lines into groups.

import itertools

def isa_group_separator(line):
    return line=='\n'

with open('data_file') as f:
    for key,group in itertools.groupby(f,isa_group_separator):
        # print(key,list(group))  # uncomment to see what itertools.groupby does.
        if not key:
            data={}
            for item in group:
                field,value=item.split(':')
                value=value.strip()
                data[field]=value
            print('{FamilyN} {Name} {Age}'.format(**data))

# Y X 20
# F H 23
# Y S 13
# Z M 25

这篇关于Python:如何遍历行块的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！