python - 在 Python 中查找两个数据帧之间的差异

Question

假设我有两个数据框

答：

column1 column2 
  abc      2
  def      2

乙：

column1 column2 
  abc      2
  def      1

我想比较这两个数据框并找出差异所在并获取 column1 的值。

所以在这种情况下输出应该是'def'

标签： pythonpandasdataframe

Answer 1

基于此答案here，您可以尝试pd.concat方法：

pd.concat([A,B]).drop_duplicates(keep=False)['column1'].unique().tolist()

输出：

# if you just want to see the differences between the dataframe
>>> pd.concat([A,B]).drop_duplicates(keep=False)
  column1  column2
1     def        2
1     def        1

# if you just want to see the differences and with only 'column1'
>>> pd.concat([A,B]).drop_duplicates(keep=False)['column1']
1    def
1    def
Name: column1, dtype: object

# if you want unique values in the column1 as a numpy array after taking the differences
>>> pd.concat([A,B]).drop_duplicates(keep=False)['column1'].unique()
array(['def'], dtype=object) 

# if you want unique values in the column1 as a list after taking the differences
>>> pd.concat([A,B]).drop_duplicates(keep=False)['column1'].unique().tolist() 
['def']