How to Combine or Merge Pandas Dataframe Columns

Python

Here we have two ways to combine existing columns as a new one. Note all the methods below can be extended to include more than two columns.

 1|  # 1. Take the sum of the columns
 2|  df['col_3'] = df['col_1'] + df['col_2']
 3|  
 4|  # 2. Take the max of the columns
 5|  df['col_3'] = df.apply(lambda x: max(x.col_1, x.col_2),axis=1)
 6|  
 7|  # 3. Take the min of the columns
 8|  df['col_3'] = df.apply(lambda x: min(x.col_1, x.col_2),axis=1)
 9|  
10|  # 4. Take the average of the columns
11|  df['col_3'] = df.apply(lambda x: (x.col_1 + x.col_2) / 2, axis=1)
detro
Pandas | Combine
Did you find this snippet useful?

Sign up for free to to add this to your code library

Remove Stop Words from Text in DataFrame Column
Python

Pandas | Nltk | Nlp

133
LightGBM Custom Loss Function
Python

LightGBM | Loss function

121
Tuning XGBoost Hyperparameters with Grid Search
Python

XGBoost | Tuning

117
How to Convert DataFrame Values Into Percentages
Python

Lambda | Percentages | Pipe

109
How to Scale Data Using Standard Scaler But Keep Column Names
Python

Scaler | Standard

79
LightGBM Hyperparameter Tuning with GridSearch
Python

Python | LightGBM | Hyperparameter tuning | Gridsearch

77
Calculating Root Mean Squared Error (RMSE) with Sklearn and Python
Python

Rmse

77
Dynamically Create Columns in Pandas Dataframe
Python

Pandas | Columns

61
How to Train a Catboost Classifier with GridSearch Hyperparameter Tuning
Python

Catboost | Hyperparameter tuning

60
Overwriting a Python Logging File Instead of Appending
Python

Logging

55