Question

我不知道为什么以下代码不起作用。我试图掩盖大熊猫数组，就像我的顾问给我看的那样，但不管我做什么都会一直出错。我会以某种方式将pandas数据帧与numpy数组混合在一起吗？我查看了如何在另一个线程中执行此操作，我似乎在做同样的事情。

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
import os

data_dir = "./data/"

incomes_file = "incomes.csv"

incomes = pd.read_csv(os.path.join(data_dir,incomes_file))

print incomes.County_Name
print incomes.County_Name[str(incomes.County_Name).isupper() != True]

我得到了这个输出：

0             ALABAMA
1      Autauga County
2      Baldwin County
3      Barbour County
4         Bibb County
5       Blount County
6      Bullock County
7       Butler County
8      Calhoun County
9     Chambers County
10    Cherokee County
11     Chilton County
12     Choctaw County
13      Clarke County
14        Clay County
...
3178    Hot Springs County
3179        Johnson County
3180        Laramie County
3181        Lincoln County
3182        Natrona County
3183       Niobrara County
3184           Park County
3185         Platte County
3186       Sheridan County
3187       Sublette County
3188     Sweetwater County
3189          Teton County
3190          Uinta County
3191       Washakie County
3192         Weston County
Name: County_Name, Length: 3193, dtype: object
Traceback (most recent call last):
  File "/Users/Avi/Desktop/Average Income By County/data_analysis.py", line 13, in <module>
    print incomes.County_Name[str(incomes.County_Name).isupper()]
  File "/Users/Avi/anaconda/lib/python2.7/site-packages/pandas/core/series.py", line 479, in __getitem__
    result = self.index.get_value(self, key)
  File "/Users/Avi/anaconda/lib/python2.7/site-packages/pandas/core/index.py", line 1171, in get_value
    return self._engine.get_value(s, k)
  File "index.pyx", line 97, in pandas.index.IndexEngine.get_value (pandas/index.c:2987)
  File "index.pyx", line 105, in pandas.index.IndexEngine.get_value (pandas/index.c:2802)
  File "index.pyx", line 146, in pandas.index.IndexEngine.get_loc (pandas/index.c:3495)
  File "index.pyx", line 357, in pandas.index.Int64Engine._check_type (pandas/index.c:6813)
KeyError: False
[Finished in 1.4s with exit code 1]
[shell_cmd: python -u "/Users/Avi/Desktop/Average Income By County/data_analysis.py"]
[dir: /Users/Avi/Desktop/Average Income By County]
[path: /usr/bin:/bin:/usr/sbin:/sbin]

Answer 1

试试这个：

incomes[ incomes.Country_Name.apply(lambda x: x.isupper()) != True ]

您无法在所有DataFrame上使用str() - （下次使用incomes.Country_Name.str）
但是没有incomes.Country_Name.str.isupper()可以做出更简单的解决方案。

为什么我不能屏蔽这个pandas dataframe列？

1 个答案: