資料框中的值移位或滯後

import pandas as pd

df = pd.DataFrame({'eggs': [1,2,4,8,], 'chickens': [0,1,2,4,]})

df

#    chickens  eggs
# 0         0     1
# 1         1     2
# 2         2     4
# 3         4     8

df.shift()

#    chickens  eggs
# 0       NaN   NaN
# 1       0.0   1.0
# 2       1.0   2.0
# 3       2.0   4.0

df.shift(-2)

#    chickens  eggs
# 0       2.0   4.0
# 1       4.0   8.0
# 2       NaN   NaN
# 3       NaN   NaN

df['eggs'].shift(1) - df['chickens']

# 0    NaN
# 1    0.0
# 2    0.0
# 3    0.0

.shift() 的第一個引數是 periods，即移動資料的空格數。如果未指定，則預設為 1。