熊猫：在同一个键上加入多个数据帧

Question

我需要使用同一个键加入5个数据帧。我在创建连接时创建了几个临时数据框。下面的代码工作正常，但我想知道是否有一个更优雅的方式来实现这一目标？谢谢！

df1 = pd.read_pickle('df1.pkl') 
df2 = pd.read_pickle('df2.pkl') 
df3 = pd.read_pickle('df3.pkl') 
df4 = pd.read_pickle('df4.pkl') 
df5 = pd.read_pickle('df5.pkl') 

tmp_1 = pd.merge(df1, df2, how ='outer', on = ['id','week']) 
tmp_2 = pd.merge(tmp_1, df3, how ='outer', on = ['id','week']) 
tmp_3 = pd.merge(tmp_2, df4, how ='outer', on = ['id','week']) 
result_df = pd.merge(tmp_3, df5, how ='outer', on = ['id','week']) 

Answer 1

使用pd.concat设置索引后

dfs = [df1, df2, df3, df4, df5] 
cols = ['id', 'weedk'] 
df = pd.concat([d.set_index(cols) for d in dfs], axis=1).reset_index() 

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包含文件读取

from glob import glob 

def rp(f): 
    return pd.read_pickle(f).set_index(['id', 'week']) 

df = pd.concat([rp(f) for f in glob('df[1-5].pkl')], axis=1).reset_index()