在python中，如何将括号中的数字转换为负数？

Question

我有一个列，其中的行具有如下字符串：

{"Manufacture":"1920","Comapany":"(BMW)","Loss":"(20)","price":"93"}
{"Manufacture":"1911","price":"20","shutdown":"(13)"}

我想将（数字）条目转换为-number 例如，在第一行输入输出将是

{"Manufacture":"1920","Comapany":"(BMW)","Loss":"-20","price":"93"}

损失分录为（20），转换为-20

第二行条目也是如此

{"Manufacture":"1911","price":"20","shutdown":"-13"}

Answer 1

试试看：

re.sub(r"\((\d+)\)", r"-\1", s)

---

示例：

s = str({"Manufacture":"1920","Comapany":"(BMW)","Loss":"(20)","price":"93"})
st = str({"Manufacture":"1911","price":"20","shutdown":"(13)"})

---

res = re.sub(r"\((\d+)\)", r"-\1", s)

---

res:

"{'Manufacture': '1920', 'Comapany': '(BMW)', 'Loss': '-20', 'price': '93'}"

---

result = re.sub(r"\((\d+)\)", r"-\1", st)

---

结果：

"{'Manufacture': '1911', 'price': '20', 'shutdown': '-13'}"

编辑：

假设您的df为：

     0
0   {"Manufacture":"1920","Comapany":"(BMW)","Loss":"(20)","price":"93"}
1   {"Manufacture":"1911","price":"20","shutdown":"(13)"}

---

def num2neg(row):
    return re.sub(r"\((\d+)\)", r"-\1", row)

df[0] = df[0].apply(num2neg)

---

df:

    0
0   {"Manufacture":"1920","Comapany":"(BMW)","Loss":"-20","price":"93"}
1   {"Manufacture":"1911","price":"20","shutdown":"-13"}