在使用 apply 函数并尝试获取 2 个输入时在 pandas 中引发 KeyError(key)

Question

我想在 .apply 函数中获取 2 个实体并检查它，但我收到了 pandas.errors.IndexingError: Too many indexers 错误。

import pandas as pd

dict2 = {
    "name": ["kambiz", "ali", "mmd", "sara"],
    "age": [19, 19, 14, 12],
}

df = pd.DataFrame(dict2)


def show_if(age, name):
    if age == 19:
        if name == "kambiz":
           return "you are kambiz and 19"
        elif name == "ali":
           return "you are ali and 19"
    else:
        return "not available"


df["19 ages"] = df.apply(lambda x: show_if(x.loc[:, x["age"]], x.loc[:, x["name"]]), axis=1)
print(df)

如何得到两个实体，然后检查它？谢谢你的帮助 。

Answer 1

不要使用apply，而是使用矢量方法：

import numpy as np

df["19 ages"] = np.where(df['age'].eq(19),
                         '19 in this group is '+df['name'],
                         'not available')

输出：

     name  age                     19 ages
0  kambiz   19  19 in this group is kambiz
1     ali   17               not available
2     mmd   14               not available
3    sara   12               not available