How to use groupby() function in a loop?

Question

What does the frame variable signify in this code?

for group, frame in df.groupby('STNAME'):
    avg = np.average(frame['CENSUS2010POP'])
    print('Counties in state ' + group + ' have an average population of ' + str(avg))

user_7964527 · Answer

frame here is sub_group, since you groupby STNAME

So the for loop here is equal to

for x in df['STNAME'].unique():
   frame=df[df.STNAME==x]
   avg = np.average(frame['CENSUS2010POP'])

How to use groupby() function in a loop?

1 Answers