pandas merge multiple dataframes
import pandas as pd
from functools import reduce
# compile the list of dataframes you want to merge
data_frames = [df1, df2, df3]
df_merged = reduce(lambda left,right: pd.merge(left,right,on=['key_col'],
how='outer'), data_frames)merge dataframe pandas
>>> df1.merge(df2, left_on='lkey', right_on='rkey')
lkey value_x rkey value_y
0 foo 1 foo 5
1 foo 1 foo 8
2 foo 5 foo 5
3 foo 5 foo 8
4 bar 2 bar 6
5 baz 3 baz 7python - join two columns and transform it as index
df = DataFrame({'var_1':['a','b','c'], 'var_2':[1, 2, 3], 'var_3':['apple', 'banana', 'pear']})
cols = ['var_1', 'var_2'] # Set columns to combine
df['combined'] = df[cols].apply(lambda row: ', '.join(row.values.astype(str)), axis=1)
# Define which column is index
df_i = df.set_index('combined')
# Set the index to None
df_i.index.names = [None]Copyright © 2021 Codeinu
Forgot your account's password or having trouble logging into your Account? Don't worry, we'll help you to get back your account. Enter your email address and we'll send you a recovery link to reset your password. If you are experiencing problems resetting your password contact us
