如何修复 linux mint 上的 python3 安装

Question

所以我已经使用 linux mint mate 一段时间了，一切正常。 因此，当我得到一个新笔记本时，我在 windows 10 旁边安装了新版本的 linux mint (19.2 - Tina)。我认为一切都很顺利。

现在，我正在尝试让它准备好使用，但它无法正常工作。

据说它带有两个版本的python：

• Python 2.7.15+
• Python 3.6.8

但是当我尝试运行一个简单的 hello world 时，为我导入了 Essentials 包，就像这样

import numpy as np
import math #as ma
import matplotlib.pyplot as plt; plt.switch_backend('agg')
import sys
import pandas as pd
import seaborn as sns; sns.set()
import powerlaw as pl
from itertools import zip_longest
import csv
import os

print('hello world')

它甚至不识别 numpy 包，我得到了以下信息：

Traceback (most recent call last):
  File "testes.py", line 1, in <module>
    import numpy as np
ModuleNotFoundError: No module named 'numpy'

所以我去了这个网站并尝试按照教程进行操作

https://packaging.python.org/tutorials/installing-packages/#id18

但是当我尝试安装 numpy 时，结果如下：

(tutorial_env) jheniffer@jheniffer-5480:~/Dropbox/teste_cros_bi$ pip install python3-numpy
Collecting python3-numpy
Exception:
Traceback (most recent call last):
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/basecommand.py", line 215, in main
    status = self.run(options, args)
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/commands/install.py", line 353, in run
    wb.build(autobuilding=True)
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/wheel.py", line 749, in build
    self.requirement_set.prepare_files(self.finder)
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/req/req_set.py", line 380, in prepare_files
    ignore_dependencies=self.ignore_dependencies))
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/req/req_set.py", line 554, in _prepare_file
    require_hashes
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/req/req_install.py", line 278, in populate_link
    self.link = finder.find_requirement(self, upgrade)
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/index.py", line 465, in find_requirement
    all_candidates = self.find_all_candidates(req.name)
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/index.py", line 423, in find_all_candidates
    for page in self._get_pages(url_locations, project_name):
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/index.py", line 568, in _get_pages
    page = self._get_page(location)
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/index.py", line 683, in _get_page
    return HTMLPage.get_page(link, session=self.session)
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/lib/python3.6/site-packages/pip/index.py", line 795, in get_page
    resp.raise_for_status()
  File "/home/jheniffer/Dropbox/teste_cros_bi/tutorial_env/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/models.py", line 935, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 404 Client Error: Not Found for url: https://pypi.org/simple/python3-numpy/

我不知道我应该怎么做才能让它运行， 我应该如何继续安装所有东西，因为我认为已经安装了基本软件包，例如 numpy，并且每隔一次我尝试通过 pip 安装一些东西（在我以前的笔记本电脑上）它只使用

pip3 install python3-numpy

我试过不带pip的选项，安装成功

(tutorial_env) jheniffer@jheniffer-5480:~/Dropbox/teste_cros_bi$ sudo apt install python3-numpy
[sudo] password for jheniffer:             
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Suggested packages:
  gfortran python-numpy-doc python3-dev python3-nose python3-numpy-dbg
The following NEW packages will be installed:
  python3-numpy
0 upgraded, 1 newly installed, 0 to remove and 287 not upgraded.
Need to get 1.943 kB of archives.
After this operation, 10,9 MB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu bionic/main amd64 python3-numpy amd64 1:1.13.3-2ubuntu1 [1.943 kB]
Fetched 1.943 kB in 4s (528 kB/s)          
Selecting previously unselected package python3-numpy.
(Reading database ... 308507 files and directories currently installed.)
Preparing to unpack .../python3-numpy_1%3a1.13.3-2ubuntu1_amd64.deb ...
Unpacking python3-numpy (1:1.13.3-2ubuntu1) ...
Setting up python3-numpy (1:1.13.3-2ubuntu1) ...
Processing triggers for man-db (2.8.3-2ubuntu0.1) ...

但是当我尝试运行 hello word 代码时，我再次收到此消息

(tutorial_env) jheniffer@jheniffer-5480:~/Dropbox/teste_cros_bi$ python3 testes.py 
Traceback (most recent call last):
  File "testes.py", line 1, in <module>
    import numpy as np
ModuleNotFoundError: No module named 'numpy'

Answer 1

看起来您可能在 pip 中使用了 apt 包名称，而不是 PyPi 包的名称。首先，检查系统上 pip 和 python 的默认版本。这可以使用pip --version 和python --version 来完成。如果两者都默认使用 Python 2.7（它们很可能是），我强烈建议尽可能使用 Python 3.6，因为 Python 2.7 将在 2020 年达到 EOL。

您可以通过命令行使用pip3 和python3 显式执行此操作。要为 Python 3 安装 numpy，请使用 pip3 install numpy。请记住，这只会为 Python 3 安装它，因此如果您启动 Python 2.7 解释器，它将不会被安装。

以后如果你想找到一个PyPi包的名字来安装，你可以pip search {QUERY}，比如pip search numpy。