熊猫-蟒蛇中一列的累计和
使用预定义的函数 cumsum() ，可以很容易地计算 Pandas 中一列的累计和。
语法: cumsum(轴=无，skipna =真，args， * * kwargs) 参数: 轴: {index (0)，columns (1)} skipna: 排除 NA/null 值。如果整行/整列为 NA，则结果为 NA 返回:该列的累计和
例 1:
蟒蛇 3
import pandas as pd
import numpy as np
# Create a dataframe
df1 = pd.DataFrame({"A":[2, 3, 8, 14],
"B":[1, 2, 4, 3],
"C":[5, 3, 9,2]})
# Computing sum over Index axis
print(df1.cumsum(axis = 0))
输出:
A B C
0 2 1 5
1 5 3 8
2 13 7 17
3 27 10 19
例 2:
蟒蛇 3
import pandas as pd
import numpy as np
# Create a dataframe
df1 = pd.DataFrame({"A":[None, 3, 8, 14],
"B":[1, None, 4, 3],
"C":[5, 3, 9,None]})
# Computing sum over Index axis
print(df1.cumsum(axis = 0, skipna = True))
输出:
A B C
0 NaN 1.0 5.0
1 3.0 NaN 8.0
2 11.0 5.0 17.0
3 25.0 8.0 NaN
例 3:
蟒蛇 3
import pandas as pd
import numpy as np
# Create a dataframe
df1 = pd.DataFrame({"A":[2, 3, 8, 14],
"B":[1, 2, 4, 3],
"C":[5, 3, 9,2]})
# Computing sum over Index axis
print(df1.cumsum(axis = 1))
输出:
A B C
0 2 3 8
1 3 5 8
2 8 12 21
3 14 17 19
