PYTHON：从 csv 表读取

Question

i would like to read a csv sheet. So far i have a loop which reads all rows from sheet and creates a specific txt file for each row.

with openCSV(file) as newData:
    reader = csv.reader(newData)
    next(reader)
    dictData = {}
    for i, row in enumerate(reader, 1)
        dictData = {'articleID' = row[0], 'Desc':row[1], ....}

thats working fine.

Now what i want is:

If there are more articleID's with the same numbers it should be added in one txt file.

How can i do this?

My CSV File:

Answer 1

I think pandas would be a perfect fit for this job

Install pip3 install pandas

Usage

import pandas as pd

df = pd.read_csv("data.csv")
df[df.duplicated(['ID'], keep=False)] #gives you all the duplicates

keep : {'first', 'last', False}, default 'first'

• first: Mark duplicates as True except for the first occurrence.
• last: Mark duplicates as True except for the last occurrence.
• False: Mark all duplicates as True.

Answer 2

Below. The code creates 3 csv files. One for each id.

import csv
from collections import defaultdict

data_by_id = defaultdict(list)
with open('c:\\temp\\temp.csv')as f:
    reader = csv.reader(f)
    next(reader)
    for row in reader:
        data_by_id[row[0]].append(row[1:])

for _id, data in data_by_id.items():
    with open('c:\\temp\\{}.csv'.format(_id), 'w') as f:
        f.write('id,description,price\n')
        for line in data:
            line.insert(0, _id)
            f.write(','.join(line) + '\n')

temp.csv

id,description,price
12,desc1,12.4
13,desc13,13.4
12,desc132,312.4
13,desc1er,5.8
11,desc1wewe,77.9