The following packages will be SUPERCEDED on the higher priority channel.

Question

I get this message all the time when I try to update packages, and usually I just continue, and everything as a whole works. But I'm worried that I accidentally created a much more complex Anaconda environment than me. This topic ( What does “the next packages will be replaced by a higher priority channel” mean? ) Mentions that other channels have a higher priority. If this is what I did, how can I cancel it?

Here is an example post:

conda install -c anaconda flask=0.12 Fetching package metadata ............. Solving package specifications: . Package plan for installation in environment C:\Users\HMGSYS\Anaconda3: The following packages will be SUPERCEDED by a higher-priority channel: conda: 4.3.8-py35_0 --> 4.2.13-py35_0 anaconda conda-env: 2.6.0-0 --> 2.6.0-0 anaconda Proceed ([y]/n)? 

However, if I don’t specify the version number, it seems to want to lower my version of the flask:

  conda install -c anaconda flask Fetching package metadata ............. Solving package specifications: . Package plan for installation in environment C:\Users\HMGSYS\Anaconda3: The following packages will be UPDATED: anaconda: 4.3.0-np111py35_0 --> custom-py35_0 anaconda The following packages will be SUPERCEDED by a higher-priority channel: conda: 4.3.8-py35_0 --> 4.2.13-py35_0 anaconda conda-env: 2.6.0-0 --> 2.6.0-0 anaconda flask: 0.12-py35_0 --> 0.11.1-py35_0 anaconda Proceed ([y]/n)? 

But my main question is not about versions of flacks, he asks what I did to put several channels, and how I just have it up to one. I saw a few comments that suggested modifying the .condarc file, but I don't have one (this is the default), so I don't think I'm creating a problem.

In case this helps, my conclusion from conda info:

Current installation:

  platform : win-64 conda version : 4.3.8 conda is private : False conda-env version : 4.3.8 conda-build version : 2.1.3 python version : 3.5.2.final.0 requests version : 2.12.4 root environment : C:\Users\HMGSYS\Anaconda3 (writable) default environment : C:\Users\HMGSYS\Anaconda3 envs directories : C:\Users\HMGSYS\Anaconda3\envs package cache : C:\Users\HMGSYS\Anaconda3\pkgs channel URLs : https://repo.continuum.io/pkgs/free/win-64 https://repo.continuum.io/pkgs/free/noarch https://repo.continuum.io/pkgs/r/win-64 https://repo.continuum.io/pkgs/r/noarch https://repo.continuum.io/pkgs/pro/win-64 https://repo.continuum.io/pkgs/pro/noarch https://repo.continuum.io/pkgs/msys2/win-64 https://repo.continuum.io/pkgs/msys2/noarch config file : None offline mode : False user-agent : conda/4.3.8 requests/2.12.4 CPython/3.5.2 Windows/10 Windows/10.0.14393 

Answer 1

The team you are writing

 conda install -c anaconda flask 

conda install tells Conda to install the package (obviously), and flask is the name of the package. Although you may not have the channels listed in your .condarc file, you tell conda to use a specific channel and give it the highest priority using the -c anaconda part of this command. Thus, conda install goes online and finds the best match packages that it can, given that you say that it should prefer packages from the anaconda channel. However, the anaconda channel does not have flask=0.12 , the highest version that they have (for your platform) is flask=0.11.1 . You can see here a list of all the versions that they have on this channel: https://anaconda.org/anaconda/flask/files

So this is what happens

 conda install -c anaconda flask=0.12 

it searches for all packages that it can find on the anaconda channel. It cannot find flask=0.12 for your platform, so since you installed it, it does nothing. However, he finds the versions of conda and conda-env on this channel, so he decides to download them from the anaconda channel because you have given it the highest priority, although the version is lower.

 conda install -c anaconda flask 

it also searches for all packages that it can find on the anaconda channel. Since you did not specify a version for flask , conda looking for the latest version that it can find on the channel you specify. Since you already have flask installed from another channel (in this case, the defaults channel), installing a version from the anaconda channel will replace your version.