一列在另一列中每次出现的总和

Question

我似乎找不到合适的措词来谷歌搜索这个问题，因为我得到的答案非常相似，但答案不正确。

我正在处理Titanic数据集，并希望对一个家庭中尚存的成员进行求和。因此数据集如下所示：

+-------------+----------+-----------+-------------+ | PassengerId | Survived | Surname | NumSurvived | +-------------+----------+-----------+-------------+ | 1 | 0 | Braund | | | 2 | 1 | Cumings | | | 3 | 1 | Heikkinen | | | 4 | 1 | Futrelle | | | 5 | 0 | Braund | | | 6 | 0 | Moran | | | 7 | 0 | Futrelle | | | 8 | 0 | Braund | | | 9 | 1 | Cumings | | +-------------+----------+-----------+-------------+

我需要像这样在NumSurvived列中汇总每个姓氏的Survived值：

+-------------+----------+-----------+-------------+ | PassengerId | Survived | Surname | NumSurvived | +-------------+----------+-----------+-------------+ | 1 | 0 | Braund | 0 | | 2 | 1 | Cumings | 2 | | 3 | 1 | Heikkinen | 1 | | 4 | 1 | Futrelle | 1 | | 5 | 0 | Braund | 0 | | 6 | 0 | Moran | 0 | | 7 | 0 | Futrelle | 1 | | 8 | 0 | Braund | 0 | | 9 | 1 | Cumings | 2 | +-------------+----------+-----------+-------------+

Answer 1

尝试：

Y

print（df）

M3()