python pandas：比较两列的相等性并产生第三个数据帧

python pandas : compare two columns for equality and result in third dataframe

提问by ravi

how to print the result in the separate dataframe after comparing it with two columns in different dataframes.

在将结果与不同数据帧中的两列进行比较后，如何在单独的数据帧中打印结果。

consider two dataframes:

考虑两个数据帧：

df1 = pd.DataFrame({'col1':['audi','cars']})  
df2 = pd.DataFrame({'col2':['audi','bike']})

print (df1)

    col1
0  audi
1  cars 

print (df2)

     col2
0   audi
1   bike

now the result should be in a different dataframe.

现在结果应该在不同的数据框中。

      col1  col2  result
0     audi  audi   no change
1     cars  bike   changed

回答by jezrael

Use concatwith numpy.where:

使用concat有numpy.where：

df = pd.concat([df1, df2], axis=1)
df['result'] = np.where(df['col1'] == df['col2'], 'no change', 'changed')
print (df)
   col1  col2     result
0  audi  audi  no change
1  cars  bike    changed