How to handle data frames

import pandas as pd
import numpy as np

Read csv file

df=pd.read_csv('〜〜〜.csv',header=None,names=('name', 'id'))

Specify the column name with names = ~ ~. header = None prevents the first line from being recognized as header.

Replace part of the data

df=df.replace('A B', 'AB')
df=df.replace('B A', 'BA')

Split the text in one column of df into two new columns

df2 = pd.concat([df, df['name'].str.split(' ', expand=True)], axis=1).drop('name', axis=1)

Extract multiple columns of df

df=df.loc[:,["Column name","Column name","Column name"]]

Combine dfs vertically

df3=pd.concat([df1, df2])

Delete duplicate lines

df=df[~df.duplicated()]

Extract rows that meet the conditions

df[df["Column name"]=="~~"]

List dataframe

df_list=df.values.tolist()

Make the list of columns array

df_list=np.array(df['Column name'])

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