问题描述

我有一台装有 OS X El Captain 的 Macbook.我认为 Python 2.7 是预装的.但是，我也安装了 Python 3.5.当我开始使用 Python 3 时，我读到如果我想安装一个包，我应该输入:

I have a Macbook with OS X El Captain. I think that Python 2.7 comes preinstalled on it. However, I installed Python 3.5 too. When I started using Python 3, I read that if I want to install a package, I should type:

pip3 install some_package

不管怎样，现在当我使用

Anyway, now when I use

pip install some_package

我为 Python 3 安装了 some_package.我的意思是我可以导入它并毫无问题地使用它.此外，当我在 Terminal 中仅键入 pip3 时，我收到了有关用法的消息:

I get some_package installed for Python 3. I mean I can import it and use it without problems. Moreover, when I type just pip3 in Terminal, I got this message about the usage:

Usage:   
  pip <command> [options]

这与我输入 pip 时得到的消息相同.

which is the same message I get when I type just pip.

这是否意味着在以前的版本中，情况有所不同，现在 pip 和 pip3 可以互换使用?如果是这样，并且为了争论，我如何为 Python 2 而不是 Python 3 安装包?

Does it mean that in previos versions, things were different, and now pip and pip3 can be used interchangeably? If so, and for the sake of argument, how can I install packages for Python 2 instead of Python 3?

推荐答案

您的 pip 是与 pip3 相同的可执行文件路径的软链接.您可以使用以下命令检查您的 pip 和 pip3 实际路径在哪里:

Your pip is a soft link to the same executable file path with pip3. you can use the commands below to check where your pip and pip3 real paths are:

$ ls -l `which pip`
$ ls -l `which pip3`

您也可以使用以下命令了解更多详情:

You may also use the commands below to know more details:

$ pip show pip
$ pip3 show pip

当我们安装不同版本的python时，我们可能会创建这样的软链接到

When we install different versions of python, we may create such soft links to

• 将默认点设置为某个版本.
• 为不同的版本制作不同的链接.

python、python2、python3

如果您对它在不同情况下的发生方式感兴趣，请在下面了解更多信息:

More information below if you're interested in how it happens in different cases:

• MacOS/Homebrew
• Fedora/CentOS
• Debian/Ubuntu

这篇关于pip 或 pip3 为 Python 3 安装包?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持跟版网！