Category: Pandas

To avoid including the index column when saving as a CSV file, you can add index=False in df.to_csv() to avoid including the index clumn when saving a Python Pandas dataframe as a CSV file. df.to_csv(‘filename.csv’, index=False) Output: brands models 0...

This tutorial shows how to fix the error when using Pandas. if using all scalar values, you must pass an index You encounter this error because you are trying to create a dataframe with all scalar values, but without adding...

This tutorial shows two methods of creating dummy variables in Python. The following shows the key syntax. Method 1: Use Numpy.where() to create a dummy variable np.where(df[‘column_of_interest’] == ‘value’ ,1,0) Method 2: Use apply() and lambda function to create a...

The following provides 3 different methods of calculating means group by two Columns in Python. Method 1: df.groupby([“column_1″,”column_2”]).mean() Method 2: df.groupby([“column_1″,”column_2”]).agg(‘mean’) Method 3: pd.crosstab(index=df[‘column_1’], columns=df[‘column_2’],values=df[‘dv’],aggfunc=’mean’) Prepare the data Output: city store sales 0 City1 store1 10 1 City1 store2 20 2...

We can use how='left' tells merge() to left merge two dataframes. The following is the Pandas syntax, in which df_1 and df_2 are two dataframes to be merged. df_1.merge(df_2, how=’left’, left_index=True, right_index=True) Step 1: Prepare the data to be left...

To save Pandas dataframe as CSV file, you can use the function of df.to_csv. The following shows the steps. df.to_csv(“file_name.csv”) Step 1: Dataframe example The following Python code is to generate the sample dataframe. The following is the print out...