Python Pandas Dataframe enrichment (from another)

I would like to enrich a dataframe (df1) from another(df2) by adding a new column in df1 and enriching it based on what I find in df2. The size of the 2 df is different as well as the name of the columns. I would like to do like a Vlookup function in Excel.

This what I’ve done but I think there is a way to optimize it :

import pandas as pd  
df1 = pd.read_csv(xxx)  
df2 = pd.read_csv(xxx)  
df1["Enrich"] = ""  
for index_1 , row_1 in df1.iterrows():  
    for index_2,row_2 in df2.iterrows():  
      if df1.loc[index_1,"filter_1"] == df2.loc[index_2,"filter_2"]:  
         df1.loc[index_1,"Enrich"] == df2.loc[index_2,"Theneededvalue"]

JavaScript
​x
 
import pandas as pd  
df1 = pd.read_csv(xxx)  
df2 = pd.read_csv(xxx)  
df1["Enrich"] = ""  
for index_1 , row_1 in df1.iterrows():  
    for index_2,row_2 in df2.iterrows():  
      if df1.loc[index_1,"filter_1"] == df2.loc[index_2,"filter_2"]:  
         df1.loc[index_1,"Enrich"] == df2.loc[index_2,"Theneededvalue"]
​

Thanks for your help !

JaNa

Answer

Without a sample it’s hard to help but vlookup can be implemented like that:

pd.merge(df1, df2, left_on='filter1', right_on='filter2', how='left')

JavaScript
 
pd.merge(df1, df2, left_on='filter1', right_on='filter2', how='left')
​

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Answer