n213

'NoneType' object is not subscriptable

df.dtypes == 'object'
df_object=df[['Suburb','Address','Type','Method','SellerG','Regionname','CouncilArea']]

for i in df_object:
    if len(df[i].unique())> 50:
    # if df[i].nunique() > 50 : 이어도 error
        df= df.drop(i, axis=1, inplace=True)
        
        
>>> 'NoneType' object is not subscriptable

원인 : df = df.drop으로 썼음
해결 : df.drop(i, axis=1, inplace=True) 이렇게 작성함

dropna

원하는 행은 꼭 subset=['컬럼명']

df.dropna(subset=['Price'],inplace=True)

중복제거

df.drop_duplicates(inplace=True)