Installation

WNTR requires 64-bit Python (tested on versions 3.7, 3.8, 3.9, and 3.10) along with several Python package dependencies. See Requirements and Optional dependencies for more information. WNTR can be installed as a Python package as briefly described below. Detailed instructions are included in the following section.

The latest release of WNTR can be installed from PyPI or Anaconda using one of the following commands in a terminal, command line, or PowerShell prompt.

  • PyPI pypi version pypi downloads

    pip install wntr

  • Anaconda anaconda version anaconda downloads

    conda install -c conda-forge wntr

Detailed instructions

Detailed installation instructions are included below.

Step 1: Setup the Python environment

Python can be installed on Windows, Linux, and Mac OS X operating systems. WNTR requires 64-bit Python (tested on versions 3.7, 3.8, 3.9, and 3.10) along with several Python package dependencies. Python distributions, such as Anaconda, are recommended to manage the Python environment. Anaconda can be downloaded from https://www.anaconda.com/products/individual. General information on Python can be found at https://www.python.org/.

Note

  • It is recommended to install Anaconda for a single user by selecting the ‘Just Me’ option during installation. If a user-writeable location is selected for installation (e.g., C:\Users\username\Anaconda3), then the ‘Just Me’ option does not require administrator privileges.

  • It is also recommended to add Anaconda to the PATH environment variable. This will facilitate access to Python from a command prompt without having to include the full path name. This can be done by either 1) selecting the ‘Add Anaconda to my PATH environment variable’ option during installation or 2) manually adding C:\Users\username\Anaconda3 to the environmental variables. Note that the first option is not recommended by Anaconda because it elevates the priority of Anaconda software over previously installed software. While the second option allows the user to define priority, this requires administrator privileges. If Anaconda is not added to the PATH environment variable, Python can be run by using the full path name (e.g., C:\Users\username\Anaconda3\python).

Anaconda includes the Python packages needed for WNTR, including NumPy, SciPy, NetworkX, pandas, and Matplotlib. For more information on Python package dependencies, see Requirements. If the Python installation does not include these dependencies, the user will need to install them. This is most commonly done using pip or conda.

Anaconda also comes with Spyder, an IDE, that includes enhanced editing and debugging features along with a graphical user interface. Debugging options are available from the toolbar. Code documentation is displayed in the object inspection window. Pop-up information on class structure and functions are displayed in the editor and console windows.

To open a Python console, open a command prompt (cmd.exe on Windows, terminal window on Linux and Mac OS X) and run ‘python’, as shown in Figure 3, or open a Python console using an IDE, like Spyder, as shown in Figure 4.

Python

Figure 3 Python console opened from a command prompt.

Spyder

Figure 4 Python console using Spyder.

Step 2: Install WNTR

WNTR can be installed using PyPI, Anaconda, or by downloading a zip file and building the source code, as described below. Information for developers can be found in the Developer instructions section.

Note

If WNTR is installed using PyPI or Anaconda (Options 1 or 2 below), the examples folder will not be downloaded. The examples can be downloaded by going to https://github.com/USEPA/WNTR, select the “Clone or download” button and then select “Download ZIP.” Uncompress the zip file using standard software tools (e.g., unzip, WinZip) and store them in a folder.

  • Option 1: Users can install WNTR from PyPI using pip, which is a command line software tool used to install and manage Python packages. It can be downloaded from https://pypi.python.org/pypi/pip.

    To install WNTR using pip, open a command line or PowerShell prompt and run:

    pip install wntr

    This will install the latest release of WNTR from https://pypi.python.org/pypi/wntr.

  • Option 2: Users can install WNTR from Anaconda using conda, which is a command line software tool used to install and manage Python packages. It can be downloaded from https://www.anaconda.com/products/individual.

    To install WNTR using conda, open a command line or PowerShell prompt and run:

    conda install -c conda-forge wntr

    This will install the latest release of WNTR from https://anaconda.org/conda-forge/wntr.

  • Option 3: Users can download and build WNTR using source files from the WNTR GitHub repository.

    To download a zip file of the main branch, go to https://github.com/USEPA/WNTR, select the “Clone or download” button and then select “Download ZIP.” This downloads a file called WNTR-main.zip. To download a specific release, go to https://github.com/USEPA/WNTR/releases and select a zip file. The zip file contains the examples folder.

    Uncompress the zip file using standard software tools (e.g., unzip, WinZip) and store them in a folder. WNTR can then be installed using pip, which is a command line software tool used to install and manage Python packages. It can be downloaded from https://pypi.python.org/pypi/pip. To build WNTR from the source files, open a command line or PowerShell prompt from within the folder that contains the setup.py file and run:

    python -m pip install .

    This runs setup.py install. The -m option runs pip as a Python script. The . indicates that the source files are in the current directory. This use of pip installs WNTR using the local source files (not from PyPI as shown in Option 1).

    Note

    WNTR includes C++ code that is built into shared object files (e.g., pyd for Windows) during the setup process. This requires that the user has a C++ compiler on their path. No compiler is needed when installing WNTR through PyPI (Option 1) or conda (Option 2).

Step 3: Test installation

To test that WNTR is installed, open a Python console and run:

import wntr

If WNTR is installed properly, Python proceeds to the next line. No other output is printed to the screen.

If WNTR is not installed properly, the user will see the following ImportError:

ImportError: No module named wntr

See Getting started for a simple example that can also be used to test installation. A full set of software tests can also be run locally to ensure proper installation, see Software tests for more details.

Developer instructions

Developers should review the Software quality assurance section before contributing to WNTR.

Developers can clone and setup the main branch of WNTR from source files using the following commands in a terminal, command line, or PowerShell prompt:

git clone https://github.com/USEPA/WNTR
cd WNTR
python -m pip install -e .
pip install -r requirements.txt

The -e option runs setup.py develop. This will install the main branch of WNTR from https://github.com/USEPA/WNTR in development mode. The requirements.txt file contains all the necessary dependencies for testing the package and building the documentation.

Note

WNTR includes C++ code that is built into shared object files (e.g., pyd for Windows) during the setup process. This requires that the developer has a C++ compiler on their path. When installing WNTR through PyPI or conda, the shared object files do not need to be built and no compiler is needed.

If the developer does NOT have a C++ compiler, or would rather use prebuilt wheels, the shared object files can be downloaded from WNTR GitHub Actions using the following steps:

  • Clone and setup the main branch of WNTR from the GitHub repository using the following commands in a terminal, command line, or PowerShell prompt (the --no-build command line argument omits the build step in the setup process):

    git clone https://github.com/USEPA/WNTR
cd WNTR
python -m pip install -e . --no-build
pip install -r requirements.txt

  • Select the latest GitHub Actions build_tests that uses the main branch from https://github.com/USEPA/WNTR/actions/workflows/build_tests.yml

  • Scroll down to “Artifacts”

  • Download the wheel that matches the desired operating system and Python version (for example, wntr_3.9_windows-latest.whl)

  • Unzip the wheel and locate the following files (which are named according to the operating system and Python version)

    • wntr/sim/aml/_evaluator.cp39-win_amd64.pyd

    • wntr/sim/network_isolation/_network_isolation.cp39-win_amd64.pyd

  • Copy these files into the matching directory in the cloned version of WNTR

To test WNTR, developers can run software tests locally using the following command:

pytest wntr

Requirements

Requirements for WNTR include 64-bit Python (tested on versions 3.7, 3.8, 3.9, and 3.10) along with several Python packages. Users should have experience using Python (https://www.python.org/), including the installation of additional Python packages. The following Python packages are required:

These packages are included in the Anaconda Python distribution.

Optional dependencies

The following Python packages are optional:

All of these packages except geopandas are included in the Anaconda Python distribution. To install optional dependencies, run:

pip install -r requirements.txt

Note

Proper installation of geopandas requires installing several geopandas dependencies, including fiona, pyproj, and shapely. See https://geopandas.org/en/stable/getting_started/install.html for more information. On Linux and Mac OS X, installing geopandas through the conda-forge channel will install the dependencies. On Windows, the dependencies must be installed manually, see https://geoffboeing.com/2014/09/using-geopandas-windows/ for more information.