pandas DataFrame.shift()函数可以把数据移动指定的位数
period参数指定移动的步幅,可以为正为负.axis指定移动的轴,1为行,0为列.
>>> import pandas as pd
>>> data1 = pd.DataFrame({
... 'a': [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
... 'b': [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
... })
>>> data1
a b
0 0 9
1 1 8
2 2 7
3 3 6
4 4 5
5 5 4
6 6 3
7 7 2
8 8 1
9 9 0
>>> data2 = data1.shift(axis=0)
>>> data2
a b
0 NaN NaN
1 0.0 9.0
2 1.0 8.0
3 2.0 7.0
4 3.0 6.0
5 4.0 5.0
6 5.0 4.0
7 6.0 3.0
8 7.0 2.0
9 8.0 1.0
>>> data2 = data1['b'].shift(axis=0)
>>> data2
0 NaN
1 9.0
2 8.0
3 7.0
4 6.0
5 5.0
6 4.0
7 3.0
8 2.0
9 1.0
Name: b, dtype: float64
>>> data1['b'] = data1['b'].shift(axis=0)
>>> data1
a b
0 0 NaN
1 1 9.0
2 2 8.0
3 3 7.0
4 4 6.0
5 5 5.0
6 6 4.0
7 7 3.0
8 8 2.0
9 9 1.0如果想往上或者往左移动,可以指定(periods=-1):
data4 = data1.shift(periods=-1, axis=0)