df.apply

http://www.cnblogs.com/wuzhiblog/p/python_new_row_or_col.html

DataFrame数据预览：

          A         B         C         D         E
0  0.673092  0.230338 -0.171681  0.312303 -0.184813
1 -0.504482 -0.344286 -0.050845 -0.811277 -0.298181
2  0.542788  0.207708  0.651379 -0.656214  0.507595
3 -0.249410  0.131549 -2.198480 -0.437407  1.628228

计算各列数据总和并作为新列添加到末尾

df['Col_sum'] = df.apply(lambda x: x.sum(), axis=1)

计算各行数据总和并作为新行添加到末尾

df.loc['Row_sum'] = df.apply(lambda x: x.sum())

最终数据结果：

                A         B         C         D         E   Col_sum
0        0.673092  0.230338 -0.171681  0.312303 -0.184813  0.859238
1       -0.504482 -0.344286 -0.050845 -0.811277 -0.298181 -2.009071
2        0.542788  0.207708  0.651379 -0.656214  0.507595  1.253256
3       -0.249410  0.131549 -2.198480 -0.437407  1.628228 -1.125520
Row_sum  0.461987  0.225310 -1.769627 -1.592595  1.652828 -1.022097