add column to dataframe pandas from another dataframe code example
Example 1: how to add a column to a pandas df
df.insert(location, column_name, list_of_values)
df.insert(0, 'new_column', ['a','b','c'])
df['new_column_name'] = value
Example 2: add column to df from another df
feature_file_df['RESULT'] = RESULT_df['RESULT'].values
feature_file_df['RESULT'] = RESULT_df['RESULT'].to_numpy()
Example 3: Adding a new column in pandas dataframe from another dataframe with different index
merge(left, right, how='left', on=None, left_on=None, right_on=None,
left_index=False, right_index=False, sort=True,
suffixes=('_x', '_y'), copy=True)