根据分组条件连接csv中的列值

Question

我有一个如下所示的csv（注意：Name列中的值不受限制，即不仅仅是ABC和DEF）：

Name, Type, Text 
ABC, Type A, how
ABC, Type A, are
ABC, Type A, you
ABC, Type B, Your
ABC, Type B, Name?
DEF, Type A, I
DEF, Type A, am
DEF, Type A, good
DEF, Type B, I'm
DEF, Type B, Terminator
... and more 

我想创建另一个csv文件，如下所示（即，基于每个Name列的Type列的组Text列）：

Name, Type, Text
ABC, Type A, how are you
ABC, Type B, Your Name?
DEF, Type A, I am good
DEF, Type B, I'm Terminator
..till the end

我正在尝试编写一个python脚本。我的尝试如下：

TypeList = ['Type A','Type B']
with open("../doc1.csv", encoding='utf-8', newline='', mode="r") as myfile:
    
    g = csv.reader(myfile)

    with open("../doc2.csv", encoding='utf-8', newline='', mode="w") as myfile:
        h = csv.writer(myfile)
        h.writerow(["Name","Text"])

        for row in g:
            if TypeList[0] in row[1]:    
               Concatenatedtext[0]= Concatenatedtext[0] + ' ' + row[1]

有人能帮我解决这个烂摊子吗

Answer 1

将csv行分组在一起是itertools.groupby函数的任务

itertools.groupby接受定义匹配行的键函数，并为找到的每个匹配项发出键（这里是名称和类型）和组（匹配的行）

operator.itemgetter函数可用于创建键函数

import csv
import itertools
import operator

# A function that gets the Name and Type values for each row:
# this is used to group the rows together.
key_func = operator.itemgetter(0, 1)

with open('myfile.csv', newline='') as f:
    reader = csv.reader(f)
    # Skip header row
    next(reader)
    for key, group in itertools.groupby(reader, key=key_func):
        text = ' '.join(cell[2] for cell in group)
        print([key[0], key[1], text])

输出：

['ABC', ' Type A', ' how  are  you']
['ABC', ' Type B', ' Your  Name?']
['DEF', ' Type A', ' I  am  good']
['DEF', ' Type B', " I'm  Terminator"]