New to Python#

Setting Up Mambaforge#

If you are new to Python and want to get started quickly, you can use Mambaforge, which is a conda-like package manager configured with conda-forge.

Step 1:

Downloaded the latest Mambaforge for your platform from Most users will use x86_64(amd64) for Intel and AMD processors. Mac users with Apple Silicon should use arm64(Apple Silicon) for best performance.

Next, complete the Mambaforge installation on your system.


Mambaforge is a drop-in replacement for conda. If you have an existing conda installation, you can replace all following mamba commands with conda and achieve the same functionality.

If you are using Anaconda or Miniconda on Windows, you should open Anaconda Prompt instead of Miniforge Prompt.

Step 2:

Open Terminal (on Linux or maxOS) or Miniforge Prompt (on Windows, not cmd!!). Make sure you are in a conda environment - you should see (base) prepended to the command-line prompt, such as (base) C:\Users\username>.

Create an environment for ANDES (recommended)

mamba create --name andes python=3.8

Activate the new environment with

mamba activate andes


You will need to activate the andes environment every time in a new Miniforge Prompt or shell.

If these steps complete without error, you now have a working Python environment. See the commands at the top to Getting started ANDES.

Extra support package#

Some ANDES features require extra support packages, which are not installed by default. For example, to build the documentation, one will need to install development packages. Other packages will be required for interoperability.

The extra support packages are specified in groups. The following group names are supported, with descriptions given below:

  • dev: packages to support development such as testing and documentation

  • interop: packages to support interoperability of ANDES and other power systems tools.


Extra support packages are not supported by conda/mamba installation. One needs to install ANDES with pip.

To install packages in the dev when installing ANDES, do:

pip install andes[dev]

To install all extra packages, do:

pip install andes[all]

One can also inspect the requirements-extra.txt to identify the packages for manual installation.

Develop Install#

The development mode installation is for users who want to modify the code and, for example, develop new models or routines. The benefit of development mode installation is that changes to source code will be reflected immediately without re-installation.

Step 1: Get ANDES source code

As a developer, you are strongly encouraged to clone the source code using git from either your fork or the original repository. Clone the repository with

git clone


Replace the URL with yours to use your fork. With git, you can later easily update the source code and perform version control.

Alternatively, you can download the ANDES source code from and extract all files to the path of your choice. Although works, this method is discouraged because tracking changes and pushing back code edits will require significant manual efforts.

Step 2: Install dependencies

In the Mambaforge environment, use cd to change directory to the ANDES root folder. The folder should contain the file.

Install dependencies with

mamba install --file requirements.txt
mamba install --file requirements-extra.txt

Alternatively, you can install them with pip:

pip install -r requirements.txt
pip install -r requirements-extra.txt

Step 3: Install ANDES in the development mode using

python3 -m pip install -e .

Note the dot at the end. Pip will take care of the rest.


The ANDES version number shown in pip list will stuck at the version that was intalled, unless ANDES is develop-installed again. It will not update automatically with git pull.

To check the latest version number, check the preamble by running the andes command or chek the output of python -c "import andes; print(andes.__version__)"


ANDES updates may infrequently introduce new package requirements. If you see an ImportError after updating ANDES, you can manually install the missing dependencies or redo Step 2.


To install extra support packages, one can append [NAME_OF_EXTRA] to pip install -e .. For example, pip install -e .[interop] will install packages to support interoperability when installing ANDES in the development, editable mode.

Updating ANDES#


If ANDES has been installed in the development mode using source code, you will need to use git or the manual approach to update the source code. In this case, Do not proceed with the following steps, as they will install a separate site-package installation on top of the development one.

Regular ANDES updates will be pushed to both conda-forge and Python package index. It is recommended to use the latest version for bug fixes and new features. We also recommended you to check the Release notes before updating to stay informed of changes that might break your downstream code.

Depending you how you installed ANDES, you will use one of the following ways to upgrade.

If you installed it from mamba or conda, run

conda install -c conda-forge --yes andes

If you install it from PyPI (namely, through pip), run

python3 -m pip install --yes andes

Uninstall Multiple Copies#

A common mistake new users make is to have multiple copies of ANDES installed in the same environment. This can happen when one previously installed ANDES in the development mode but later ran conda install or python3 -m pip install to install the latest version. As a result, only the most recently installed version will be accessible.

In this case, we recommend that you uninstall all version and reinstall only one copy using your preferred mode. Uninstalling all copies can be done by calling conda remove andes and python3 -m pip uninstall andes. The prompted path will indicate the copy to be removed. One may need to run the two commands for a couple of time until the package managers indicate that the andes package can no longer be found.


If you get an error message on Windows, reading

ImportError: DLL load failed: The specified module could not be found.

It is a path issue of your Python. In fact, Python on Windows is so broken that many people are resorting to WSL2 just for Python. Fixes can be convoluted, but the easiest one is to install ANDES in a Conda/Mambaforge environment.