官方文档
将轴上的两个对象与每个轴索引的指定连接方法连接
DataFrame.align(other, join='outer', axis=None, level=None, copy=True, fill_value=None, method=None, limit=None, fill_axis=0, broadcast_axis=None
例子:
data1 = pd.DataFrame(np.ones((6,3),dtype=float),columns = ['a','b','c'],index = pd.date_range('6/12/2012',periods =6))
data1
data2 = pd.DataFrame(np.ones((6,3),dtype = float) *2 ,columns=['a','b','c'],index=pd.date_range('6/13/2012',periods=6))
data2
data1.align(data2) #默认连接是outer
data1.align(data2,fill_value = "S") ##用s填补空值
data1.align(data2,method = 'ffill',limit =1) ##填补空值的上限
data1.align(data2,axis=1) #Align on data2 columns (1)
data1.align(data2,axis=0) #Align on data2 index (0)
data1.align(data2,join = 'inner') ##用inner的方式连接