vlookup在2个数据帧之间的pandas中创建第三个数据帧

时间:2017-11-17 01:41:27

标签: python python-3.x pandas

我想使用excel的vlookup等效的新数据帧。我有2个数据框,我正在尝试针对df1.Column A valuedf2.Column A and B进行v-lookup Value A并获取df1.Column A

旁边的单元格df2.Column A and Bvalue B并获得Current ouput Data frame 1 Dataframe2 AC1 AC2 AC10 AC20 Bus 5 car 1 car 3 helicopter 7 Walking 2 running 5

数据看起来像 -

对于数据帧1和2,数据分别在A列和B列中

           Dataframe [Neu]    

NaNa                       NaNa    
Car                           1     
NaNa                       NaNa

期望/预期输出

dfz = df1.insert(2, '2A2', df1['AC1'].map(df2.set_index('AC1')['2A2']))
print (dfz)

result = left.join(right, on=['AC2', 'AC1], how='inner')
#left.join(right, lsuffix='_l', rsuffix='_r')

#df1.join(df1.set_index('AC2')['AC1'], on='AC2')

我试过了:

df8 = df1['AC3'] = df1.AC1.map(df2.AC10)
print (df8)


df8 = df1['AC4'] = df1.AC1.map(df2.AC20)
print (df8)

我取得了一些成功:

df1 = pd.read_excel('C:/Users/Desktop/zav.xlsx')

df2 = pd.read_excel('C:/Users/Desktop/zav2.xlsx')

#df3 = pd.merge(df, df2)
df3 = df1.join(df2)
print (df3)


todays_date = datetime.datetime.now().date()
index = pd.date_range(todays_date-datetime.timedelta(10), periods=10, freq='D')

df5 = pd.DataFrame(np.random.randint(low=0, high=10, size=(5, 5)),
                 columns=['a', 'b', 'c', 'd', 'e'])
print(df5)


df8 = df1['AC3'] = df1.AC1.map(df2.AC10)
print (df8)


df8 = df1['AC3'] = df1.AC1.map(df2.AC20)
print (df8)

确切的输出是NaN,所以它不正确。

示例:

UISlider

1 个答案:

答案 0 :(得分:1)

您可以查看以下使用map的代码:

import pandas as pd    

df1 = pd.DataFrame([["Bus",5],["car",3],["Walking",2]],columns=["AC1","AC2"])

df2 = pd.DataFrame([["car",1],["helicopter",7],["running", 5]],columns=["AC10","AC20"])

df2 = df2.groupby("AC10").first()

df3= df1.join(df2,on="AC1",how="left").drop("AC2",axis=1)

它将输出以下内容:

       AC1  AC20
0      Bus   NaN
1      car   1.0
2  Walking   NaN