Pandas 添加列错误必须与键的长度相同？

Question

当我尝试拆分一列并在当前数据框中创建其他列时出现此错误：

列的长度必须与键的长度相同

if 'FULLNAME' in dataset.columns:
       dataset[['FIRSTNAME','LASTNAME']] = dataset.FULLNAME.str.split(" ", 1)

在我设置静态列名称之前：

dataset.columns = ["NUM", "MMYY", "AGE", "FULLNAME", "ADDRESS", "CITY", "STATE", "ZIP", "COUNTRY", "PHONE"]

怎么装？

我想有些列还没有FULLNAME提取

可能是用这个：

dataset["FIRSTNAME"] = None
dataset["LASTNAME"] = None

if 'FULLNAME' in dataset.columns:
    r = dataset.FULLNAME.str.split(" ", 1)
    if (r[0]):
        dataset["LASTNAME"] = r[0]
    if (r[1]):
        dataset["FIRSTNAME"] = r[1]

数据集是：

"NUM", "MMYY", "AGE", "FULLNAME", "ADDRESS", "CITY", "STATE", "ZIP", "COUNTRY", "PHONE"

1 1010 18 OLEG Kirova Wage US 1911 US +9584345345
2 1011 19 Krina Kirova Wage US 1911 US +9584345345
3 1012 20 Marina Kirova Wage US 1911 US +9584345345

Answer 1

我想你想将 expand=True 传递给 split 以便它 returns 一个 DataFrame...

if 'FULLNAME' in dataset.columns:
       dataset[['FIRSTNAME','LASTNAME']] = dataset.FULLNAME.str.split(" ", 1, expand=True)

Pandas 添加列错误必须与键的长度相同？

Pandas add columns error must be same length as key?

python

pandas