Python pandas - filter rows after groupby

Question

For example I have following table:

index,A,B
0,0,0
1,0,8
2,0,8
3,1,0
4,1,5

After grouping by A:

0:
index,A,B
         


        

Answer 1

All of these answers are good but I wanted the following:

(DataframeGroupby object) --> filter some rows out --> (DataframeGroupby object)

Shrug, it appears that is harder and more interesting than I expected. So this one liner accomplishes what I wanted but it's probably not the most efficient way :)

gdf.apply(lambda g: g[g['team'] == 'A']).reset_index(drop=True).groupby(gdf.grouper.names) 

Working Code Example:

import pandas as pd

def print_groups(gdf): 
    for name, g in gdf: 
        print('\n'+name) 
        print(g)

df = pd.DataFrame({'name': ['sue', 'jim', 'ted', 'moe'],
                   'team': ['A', 'A', 'B', 'B'], 
                   'fav_food': ['tacos', 'steak', 'tacos', 'steak']})                               

gdf = df.groupby('fav_food')                                                                                                                                           
print_groups(gdf)                                                                                                                                                      

    steak
        name team fav_food
    1  jim    A    steak
    3  moe    B    steak

    tacos
        name team fav_food
    0  sue    A    tacos
    2  ted    B    tacos

fgdf = gdf.apply(lambda g: g[g['team'] == 'A']).reset_index(drop=True).groupby(gdf.grouper.names)                                                                      
print_groups(fgdf)                                                                                                                                                     

    steak
      name team fav_food
    0  jim    A    steak

    tacos
      name team fav_food
    1  sue    A    tacos