Both the miniconda3 and minforge modules include only conda, python, and a few other packages. Only the miniforge module provides mamba.
Mamba is a drop-in replacement of conda, and is faster at resolving dependencies than conda. For commands like conda install
and conda search
, conda
can be replaced with mamba
on Oscar. More details can be found in Mamba User Guide.
It is not recommended to initialize conda via conda init
.
To access the conda or mamba command, load either a miniconda3 or miniforge module and then run the source command
shared among all users if the environment is installed in a shared directory
private to one user if the environment is installed in a user's private directory
The command 'conda info' shows important configurations for conda environment.
Below are some important configurations:
envs directories
: a list of directories where a conda environment is installed by default. In the output of 'conda info' above, the first default directory to install a conda environment is a $HOME/anaconda.
package cache
: a list of directories where downloaded packages are stored.
To create a new conda environment in a default directory, run the following command:
To create a new conda environment in a different directory, run the following command:
After creating a conda environment, users can activate a conda environment to install or access packages in the environment via the following command.
The commands above will only work if:
A conda environment with the specified name (conda_environment_name
in the example) exists
The appropriate anaconda module has been loaded (if you are unsure about this one, consult this documentation)
If you need to activate a conda environment in a bash script, you need to source the conda.sh as shown in the following example bash script:
module load miniconda3/23.11.0s
source /oscar/runtime/software/external/miniconda3/23.11.0/etc/profile.d/conda.sh
conda activate my_env
module load miniforge/23.11.0-0s
source /oscar/runtime/software/external/miniforge/23.11.0-0/etc/profile.d/conda.sh
conda activate my_env
After installing packages in an active environment (instructions below), you do not need to load or install those packages in the bash script; any packages installed in the conda environment (before the script even starts) will be available through the environment after it is activated (line 4 in the code above).
Do NOT activate a conda environment before submitting a batch job if the batch job activates a conda environment. Otherwise, the batch job will not be able to activate the conda environment and hence fail.
To deactivate a conda environment, simply use the following command:
To install a package, we need to first activate a conda environment, and then run
conda install package_name=version
mamba install package_name=version
The "=version" is optional. By default, conda install a package from the anaconda channel. To install a package from a different channel, run conda install
with the -c
option. For example, to install a package from the bioconda channel, run
conda install -c bioconda package_name
mamba install -c bioconda package_name
To delete a conda environment, run
Conda may download lots of additional packages when installing a package. A user may use up all quota due to these downloaded packages. To remove the downloaded packges, run