17 lines
506 B
Python

def add_constant_column(df):
"""
Adds a constant column 'const' with value 1 as the first column to the DataFrame.
Parameters:
df (pd.DataFrame): Input DataFrame.
Returns:
pd.DataFrame: DataFrame with the added constant column as the first column.
"""
# Create a new DataFrame to avoid modifying the original DataFrame
df_with_const = df.copy()
# Add a constant column with value 1
df_with_const.insert(0, 'const', 1)
return df_with_const