Python 使用 Pandas 合并两个 csv 文件
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Combining two csv files using pandas
提问by Fiqri Mfbw
Can anyone check for me what's wrong with my code. I want it merge two csv file into one csv file.
任何人都可以检查我的代码有什么问题。我希望它将两个 csv 文件合并为一个 csv 文件。
I hve tried to google and I still cant merge it, it will create new file but will show nothing inside.https://stackoverflow.com/a/16266144/7624469
我试过谷歌，但我仍然无法合并它，它会创建新文件但里面什么也不显示。https://stackoverflow.com/a/16266144/7624469
a.csv
一个.csv
ID User
A1 Fi
A2 Ki
b.csv
b.csv
ID User
A4 Fsdi
A5 Kisd
The output that I want will look like this
combined.csv
我想要的输出看起来像这样
合并.csv
ID User
A1 Fi
A2 Ki
A4 Fsdi
A5 Kisd
test.py
测试文件
import pandas, sys
import pandas as pd
a = pd.read_csv("C:/JIRA Excel File/a.csv")
b = pd.read_csv("C:/JIRA Excel File/b.csv")
merged = a.merge(b, on='ID')
merged.to_csv('C:/JIRA Excel File/result.csv', index=False)
回答by cs95
Using df.append:
使用df.append：
out = df1.append(df2)
print(out)
ID User
0 A1 Fi
1 A2 Ki
0 A4 Fsdi
1 A5 Kisd
with open('C:/JIRA Excel File/result.csv', 'w', encoding='utf-8') as f:
out.to_csv(f, index=False)
回答by Grigory
It is better to use pd.concathere to combine this frames, not merge:
最好在pd.concat这里使用来组合这些帧，而不是merge：
merged = pd.concat([a,b])
Toy example with your data:
您的数据的玩具示例：
a = pd.DataFrame([['Fi'],['Ki']],columns=['User'], index=['A1','A2'],) #'ID')
b = pd.DataFrame([['Fi'],['Ki']],columns=['User'], index=['A4','A5'],) #'ID')
pd.concat([a,b])
Will output:
将输出：
User
A1 Fi
A2 Ki
A4 Fi
A5 Ki
