To do it with no questions asked

conda env remove --name foo --yes

Ask for confirmation

conda env remove --name foo

If the environment was installed in a non standard location

conda env remove -p foo

where foo is the path of the environment.

tags | delete

related commands:

conda info --envs
conda remove --help

conda env update -f environment.yml

where environment.yml is the path of the environment file

Ref:- https://conda.io/docs/commands/env/conda-env-update.html

conda update -n <env_name> -c defaults --yes conda

For example

conda update -n base -c defaults --yes conda

To specify a particular version number, X.Y.Z (ex:- 4.5.4)

conda update -n base -c defaults --yes conda=X.Y.Z

To downgrade to a specific version

conda config --set allow_conda_downgrades true
conda install -n base -c defaults conda=4.6.14

tags | upgrade conda

Ref:-

• https://anaconda.org/anaconda/conda - shows the latest conda version available

tags | check package version, list packages in environment, show the package version

To find the version of a package installed

conda list -n env_name package_name

For example

$ conda list pandas -n py39
# packages in environment at C:\ProgramData\Continuum\Anaconda\envs\py39:
#
# Name                    Version                   Build  Channel
pandas                    1.2.4            py39hd77b12b_0
pandas-datareader         0.9.0                      py_0

You can also use this technique to check if a package is installed.

For multiple packages

conda list -n env_name | grep -E "pkgA|pkgB"

For example

$ conda list -n py39 | grep -E "pandas|numpy"
numpy                     1.20.1           py39h34a8a5c_0
numpy-base                1.20.1           py39haf7ebc8_0
pandas                    1.2.4            py39hd77b12b_0
pandas-datareader         0.9.0                      py_0

Ref:- https://conda.io/docs/commands/conda-list.html

conda clean --dry-run --all
conda clean --all

Ref:-

• https://stackoverflow.com/questions/48706548/how-to-free-disk-space-taken-up-by-anaconda
• https://github.com/conda/conda/issues/8630 - recommends conda clean –all to fix conda json.decoder.JSONDecodeError: Unterminated string starting at: line xxxxxx column xx (char xxxxxxxx)

name: sample_py36
channels:
  - conda-forge
  - defaults
dependencies:
  - python=3.6.8
  - pandas=0.24.1
  - pip:
    - pywinauto
    - fastavro==0.21.18

conda info

tags | conda cache directory

Related commands:

conda clean --all --dry-run
conda clean --packages --dry-run

$ conda info | grep "user config file"
       user config file : C:\Users\raju\.condarc

• conda install - https://docs.conda.io/projects/conda/en/latest/commands/install.html
• conda update - https://docs.conda.io/projects/conda/en/latest/commands/update.html
• conda config - https://docs.conda.io/projects/conda/en/latest/commands/config.html
• pinning packages - https://docs.conda.io/projects/conda/en/latest/user-guide/tasks/manage-pkgs.html#preventing-packages-from-updating-pinning

tags | activate conda environment through shell script

For conda >= 4.4.0, use “conda activate” instead of “source activate”. The former is faster and the command remains same across OSes.

From https://github.com/conda/conda/blob/master/CHANGELOG.md#440-2017-12-20 → “New Feature Highlights” section

conda activate: The logic and mechanisms underlying environment activation have been reworked. With conda 4.4, conda activate and conda deactivate are now the preferred commands for activating and deactivating environments. You'll find they are much more snappy than the source activate and source deactivate commands from previous conda versions. The conda activate command also has advantages of (1) being universal across all OSes, shells, and platforms, and (2) not having path collisions with scripts from other packages like python virtualenv's activate script.

See also: conda activate, source activate

# As described in https://github.com/conda/conda/issues/8186
# The conda activate command is failing with
# conda.sh: line 55: PS1: unbound variable
# Until the issue is fixed, set +eu before calling "source activate"
# and set -eu afterwards
set +eux
# If the conda.sh is not sourced, then 'conda activate' is giving
# CommandNotFoundError: Your shell has not been properly configured
# to use 'conda activate'.
source "$(dirname $(which conda))/../etc/profile.d/conda.sh"
conda activate $ENV_NAME
set -eux

tested with conda 4.8.3 on a machine running RHEL 7.6

See also: source activate vs. conda activate, source activate

# As described in https://github.com/conda/conda/issues/8186
# The conda activate command is failing with
# conda.sh: line 55: PS1: unbound variable
# Until the issue is fixed, set +eu before calling "source activate"
# and set -eu afterwards
set +eux
source activate $ENV_NAME
set -eux

tested with conda 4.8.3 on a machine running RHEL 7.6

See also: source activate vs. conda activate, conda activate

Sample commands:

conda create -n <myenv> python ipython prompt_toolkit=2 jupyter pandas numpy scipy scikit-learn matplotlib

conda create -n <myenv> python=3.9 pandas pandas-datareader

$ conda config --add pinned_packages defaults::conda

To revert

$ conda config --remove-key pinned_packages

• https://docs.conda.io/projects/conda/en/latest/commands.html#conda-vs-pip-vs-virtualenv-commands → scroll down to see a table that shows how to accomplish different tasks by using either conda or a combination pip and virtualenv.