pandas python pandas数据框连接两个数据框
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python pandas dataframe join two dataframes
提问by bjurstrs
I am trying to join to data frames. They look like this
我正在尝试加入数据框。他们看起来像这样
DF1 = ID COUNTRY YEAR V1 V2 V3 V4
12 USA 2012 x y z a
13 USA 2013 x y z a
14 RUSSIA 2012 x y z a
DF2 = ID COUNTRY YEAR TRACT
9 USA 2000 A
13 USA 2013 B
The desired end goal is:
期望的最终目标是：
DF3 = ID COUNTRY YEAR V1 V2 V3 V4 TRACT
9 USA 2000 A
12 USA 2012 x y z a
13 USA 2013 x y z a B
14 RUSSIA 2012 x y z a
I've been trying to use the pd.merge and the .join function with the on='outer' setting to no success
我一直在尝试使用 pd.merge 和 .join 函数与 on='outer' 设置没有成功
df3 = pd.merge(df1,df2,how='outer',left_on=['ID','Country','Year'],right_on=['ID',"Country","Year"])
采纳答案by JAB
try this:
尝试这个：
df.merge(df2,how='outer',left_on=['ID','COUNTRY','YEAR'],right_on=['ID',"COUNTRY","YEAR"])
(the column names should be in caps based on your input tables)
（列名应根据您的输入表大写）
回答by Harvey
Have you tried
你有没有尝试过
df1.join(df2)
You can add parameters later, but it should work.
您可以稍后添加参数，但它应该可以工作。
