Python 3：获取与pandas dataframe某列中的值关联的索引名称

Question

I am trying to get a list of the corresponding index names of 500,000 values out of 2,000,000 entries in a pandas dataframe which are located in a specific column names "entity_id" (out of 1000+ columns). My solution has been the following code:

    index_names_list= []
    for id in id_dataframe:
         index_names_list.append(full_data[full_data['entity_id'] == id ].index.values)

However, this runs very very slow. Can anyone suggest a better and more efficient way of doing it?

Answer 1

try this,

full_data.loc[full_data['entity_id'].isin(id_dataframe),:].index.tolist()