dataFrame多行合并成一行

 

df = pd.DataFrame({'Team': ['A', 'A', 'B'], 'score': ['90', '80', '80'],'name':['1','2','3']})

df = df.groupby("Team")['score'].apply(lambda x:",".join(x)).str.split(",",expand=True)
df = df.reset_index()

df.rename(columns={0:"分数1",1:"分数2"},inplace=True)
print(df)
print(df.columns)


合并后的某列的值是多个，但是只取第一个

risk_weights = risk_weights.groupby(['risk_type', 'risk_factor'])['risk_weight'].apply(
    lambda x: x.iloc[0])

risk_weights = risk_weights.reset_index()