康达卸载和安装时，软件包不匹配

Question

在打开jupyter notebook时有一个ImportError，所以我跟着here跑了conda uninstall pyzmq->conda install pyzmq

我使用了conda而不是pip，因为人们说，“不要在conda环境下混淆conda和pip命令”

然后我意识到conda uninstall pyzmq和conda install pyzmq的包是不同的：

• conda uninstall pyzmq19已删除包
• conda install pyzmq；仅安装了3个软件包

为什么通过同一个conda命令安装和卸载的软件包不同？
他们不应该安装并重新安装相应的软件包吗？

我对Anaconda还是相当陌生的，如果您有更好的conda环境管理的诀窍来最小化环境损坏的风险，我们非常感谢您的建议。

---

当conda uninstall

(my_env) C:\Users\koyamashinji>conda uninstall pyzmq
Collecting package metadata (repodata.json): done
Solving environment: done

## Package Plan ##
  environment location: C:\Users\koyamashinji\anaconda3\envs\my_env
  removed specs:
    - pyzmq

The following packages will be REMOVED:

  colorama-0.4.4-py_0
  decorator-4.4.2-py_0
  ipykernel-5.3.4-py36h5ca1d4c_0
  ipython-5.8.0-py36_1
  ipython_genutils-0.2.0-pyhd3eb1b0_1
  jupyter_client-6.1.7-py_0
  jupyter_core-4.7.0-py36haa95532_0
  libsodium-1.0.18-h62dcd97_0
  pickleshare-0.7.5-pyhd3eb1b0_1003
  prompt_toolkit-1.0.15-py_1
  pygments-2.7.2-pyhd3eb1b0_0
  python-dateutil-2.8.1-py_0
  pywin32-227-py36he774522_1
  pyzmq-20.0.0-py36hd77b12b_1
  simplegeneric-0.8.1-py36_2
  tornado-6.1-py36h2bbff1b_0
  traitlets-4.3.3-py36_0
  wcwidth-0.2.5-py_0
  zeromq-4.3.3-ha925a31_3

当conda install

(my_env) C:\Users\koyamashinji>conda install pyzmq
Collecting package metadata (current_repodata.json): done
Solving environment: done

## Package Plan ##

  environment location: C:\Users\koyamashinji\anaconda3\envs\my_env

  added / updated specs:
    - pyzmq


The following NEW packages will be INSTALLED:

  libsodium          pkgs/main/win-64::libsodium-1.0.18-h62dcd97_0
  pyzmq              pkgs/main/win-64::pyzmq-20.0.0-py36hd77b12b_1
  zeromq             pkgs/main/win-64::zeromq-4.3.3-ha925a31_3

Answer 1

Why do packages installed and uninstalled via same conda command differ?Shouldn't they install and reinstall exactly corresponding packages?

conda install和conda uninstall应该安装和卸载完全对应的软件包，只要环境没有被破坏
我的环境已经坏了，可能是因为我以前使用pip安装了一些与jupyter相关的软件包（正如您可以看到的，一些软件包是py_0，这意味着它们是通过pip install安装的。）

---

I am still pretty new to Anaconda, if you have any tricks for a better conda envs management to minimize the risk of broken envs, your advise is greatly appreciated.

我花了整整一周的时间试图弄清楚它们是如何工作的，下面是我得到的（现在）

• 确保在创建环境时指定Anaconda支持的python版本。
  选中here并在conda create -n my_env python==version时指定python版本

• 确保在创建环境时也安装了所有已知的必需软件包
  conda create -n my_env python=version package_A, package_B ...
  正如Official document所说的“同时安装此环境中所需的所有程序。一次安装一个程序可能会导致依赖关系冲突。”

• 确保您完全理解conda install/uninstall和pip install/uninstall所做的事情。

conda install/uninstall

(my_env) C:\Users> conda install package_A  

# Installs : package_A + dependencies(dependency_1, dependency_2, dependency_3)
  

(my_env) C:\Users> conda uninstall package_A

# Uninstalls : package_A + dependencies(dependency_1, dependency_2, dependency_3)

(my_env) C:\Users> conda install package_A

# Installs : package_A + dependencies(dependency_1, dependency_2, dependency_3)    
  

(my_env) C:\Users> conda uninstall dependency_1

# Uninstalls : package_A + dependencies(dependency_1, dependency_2, dependency_3)

pip install/uninstall

(my_env) C:\Users> pip install package_A  

# Installs : package_A + dependencies(dependency_1, dependency_2, dependency_3)
  

(my_env) C:\Users> pip uninstall package_A

# Uninstalls : package_A ONLY

(my_env) C:\Users> pip install package_A

# Installs : package_A + dependencies(dependency_1, dependency_2, dependency_3)    
  

(my_env) C:\Users> pip uninstall dependency_1

# Uninstalls : dependency_1 ONLY