Python 如何更改.csv文件所有示例中的特定元素?
作为输入,我有一个.csv文件,如:Python 如何更改.csv文件所有示例中的特定元素?,python,csv,pandas,Python,Csv,Pandas,作为输入,我有一个.csv文件,如: user, withdraw, date 50D8BF0DA22D6C914777D8F59DAAB4D8, -125, 01-02-2015 674BCF0CD236621E5680073334A73C32, -5, 01-02-2015 E17E1691D35FB2FB675E3B787B8BEDF1, -845, 01-02-2015 50D8BF0DA22D6C914777D8F59DAAB4D8, -250, 01-02-2015 674BCF0C
user, withdraw, date
50D8BF0DA22D6C914777D8F59DAAB4D8, -125, 01-02-2015
674BCF0CD236621E5680073334A73C32, -5, 01-02-2015
E17E1691D35FB2FB675E3B787B8BEDF1, -845, 01-02-2015
50D8BF0DA22D6C914777D8F59DAAB4D8, -250, 01-02-2015
674BCF0CD236621E5680073334A73C32, -98, 01-02-2015
50D8BF0DA22D6C914777D8F59DAAB4D8, -17, 01-02-2015
我想识别所有类似的“散列”代码,并将它们更改为标签,如“user1”、“user2”、“user3”……等等
我一直在尝试这样做,但在熊猫身上没有成功。知道我能做些什么吗?首先将CSV读入以下内容:
df = pd.read_csv('/path/to/file.csv', skipinitialspace=True)
收益率:
In [84]: df
Out[84]:
user withdraw date
0 50D8BF0DA22D6C914777D8F59DAAB4D8 -125 01-02-2015
1 674BCF0CD236621E5680073334A73C32 -5 01-02-2015
2 E17E1691D35FB2FB675E3B787B8BEDF1 -845 01-02-2015
3 50D8BF0DA22D6C914777D8F59DAAB4D8 -250 01-02-2015
4 674BCF0CD236621E5680073334A73C32 -98 01-02-2015
5 50D8BF0DA22D6C914777D8F59DAAB4D8 -17 01-02-2015
现在我们可以分解用户列:
并将DF写回csv:
df.to_csv('/path/to/file_new.csv', index=False)
您首先需要按如下方式构建用户词典:
import csv
hashes = {}
user_number = 1
entries = []
with open('input.csv', 'rb') as f_input:
csv_input = csv.reader(f_input, skipinitialspace=True)
header = next(csv_input)
for row in csv_input:
user = row[0]
if user not in hashes:
hashes[user] = "user{}".format(user_number)
user_number += 1
row[0] = hashes[user]
entries.append(row)
with open('output.csv', 'wb') as f_output:
csv_output = csv.writer(f_output)
csv_output.writerow(header)
csv_output.writerows(entries)
为您提供一个output.csv,其中包含:
user,withdraw,date
user1,-125,01-02-2015
user2,-5,01-02-2015
user3,-845,01-02-2015
user1,-250,01-02-2015
user2,-98,01-02-2015
user1,-17,01-02-2015
我不相信你能更新。而是读取、修改和替换://docs.python.org/3/library/csv.html和https://stackoverflow.com/questions/16020858/inline-csv-file-editing-with-pythonThanks对于support@DavyM,我不知道人们为什么投票反对它。无论如何,回答你的问题,我想更改.csv,或者生成一个新的。说真的,有什么线索说明人们为什么讨厌我的帖子吗?=/。我真的很想知道我做错了什么。还有,我应该删除它吗?非常感谢!!工作得很好。@Rogerameidalete,很高兴我能帮上忙:
user,withdraw,date
user1,-125,01-02-2015
user2,-5,01-02-2015
user3,-845,01-02-2015
user1,-250,01-02-2015
user2,-98,01-02-2015
user1,-17,01-02-2015