Conda

At installation (Anaconda), conda creates a generic environment called base which is activated by default. Therefore, when installing a package with conda install, the package will be installted in that environment. You can be more explicit and activate the environment by typing conda activate or conda activate base in a terminal.

To have a full in depth introduction to environment management with conda read the official docs: Manage Environments.

Conda Environments

Create

Create an environment from file

conda env create -f condaenv.yml

Create an empty environment

conda create -n <envname>
conda create -n <envname> python=3.6.5

Rename

You can't! You need to clone the environment and give a new name:

conda create --name <new_envname> --clone <old_envname>
conda remove --name <old_envname> --all

Delete

conda env remove --name <envname>

Export

conda env export > condaenv.yml

The file contains the parameter prefix at the end of the file which points to your local installation. This information can be ignored or removed from the file without any impact when creating a new environment on a different machine.

Commands

Update

Update all Conda packages

conda update --all

Update Anaconda only

conda update conda
conda update anaconda

Info

Get information about conda installation

conda info

Search

Search a package within the configured channels

conda search <package>

Install

Install a package

conda install <package>
conda install -c <channelname> <package>$
conda install -c conda-forge <package>

Remove

Remove a package

conda remove nodejs npm

List

List conda environments

conda env list

List current environment packages

conda list
conda -n <envname> list

Configuration

Create a conda configuration file .condarc

conda config

Get all conda configuration

conda config --get

Add channel

conda config --add channels <channelname>

Channels

To see the configured channels use the command conda info.

The defaults channel points to several channels at the repo.anaconda.com repository.

Channel	Description
pkgs/main	Includes packages built by Anaconda, Inc. with the new compiler stack
pkgs/msys2	Windows only. Included in conda's defaults channel. Necessary for Anaconda, Inc.'s R conda packages and some others in pkgs/main and pkgs/free
pkgs/r	Microsoft R Open conda packages and Anaconda, Inc.'s R conda packages.

Defaults channels (https://repo.anaconda.com/pkgs/)

Channel	Description
conda-forge	A community repository that provides conda packages for a wide range of software. (conda forge info)
anaconda	A mirror of the packages available in main, free, and pro hosted on repo.anaconda.com

Other channels

Custom config

Official docs about conda configuration: Configuration User-Guide

If you have a very fast SSD, you might increase the number of threads to shorten the time it takes for conda to create environments and install/remove packages (conda config info).

Run conda with 6 thread (use number of processors available)
conda config --set default_threads 6

# Add ``conda-forge`` channel but with lowest priority:
conda config --append channels conda-forge

Conda env in Jupyter lab

Warning

You Jupterlab can become cluttered. It is not recommended

If you want all your conda environments to be listed in Jupyter notebook and lab, make sure you've installed the packages ipykernel and nb_conda_kernels in the environment from which you run Jupyter.

conda install -n myenv ipykernel nb_conda_kernels

It is recommanded to add the kernel manually and give an explicit name. To do so, while in the environment, run the following command:

python -m ipykernel install --user --name=<envname>