Installation guide

The weldx package can be installed using conda or mamba package manager from the conda-forge channel. These managers originate from the freely available Anaconda Python stack. If you do not have Anaconda or Miniconda installed yet, we ask you to install Miniconda-3. Documentation for the installation procedure can be found here.

After this step you have access to the conda command and can proceed to installing the WelDX package:

conda create -n weldx -c conda-forge weldx

The package is also available on pypi and can be installed via pip:

pip install weldx

As weldx currently depends on the package bottleneck, which contains C/C++ code, you will need a working C/C++ compiler. The conda package does not have this requirement as it only installs pre-compiled binaries. So if you do not know how to install a working compiler, we strongly encourage using the conda package.

Setting up Jupyter Lab

Weldx provides lots of visualization methods for planning and analysis. These methods need a frontend like Jupyter lab or Jupyter notebook. We currently recommend to use Jupyter lab, as it is modern and makes working with several notebooks easier. You can install Jupyter lab both via conda or pip. If you use conda we suggest that you create a separate environment for your weldx installation and jupyter. This keeps the environments clean and easier to upgrade (is that really true? think of mixed versions of extensions in lab env and weldx env!).

Here is a guide on howto setup different kernels for Jupyter guide.

Create an environment named “jlab” via conda that installs jupyterlab and the k3d extension:

conda create -n jlab jupyterlab k3d -c conda-forge

Then we switch to the weldx environment created in the first step and make it available within Jupyter:

conda activate weldx
python -m ipykernel install --user --name weldx --display-name "Python (weldx)"

This will enable us to select the Python interpreter installed in the weldx environment within Jupyter. So when a new notebook is created, we can choose “Python (weldx)” to access all the software bundled with the weldx Python package.

fixing DLL errors on Windows systems

In case you run into an error when using the weldx kernel on Windows systems that fails to read DLLs like:

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

you might have to apply the fix mentioned here.

Go to %userprofile%\.ipython\profile_default\startup using the windows explorer and create a new file called ipython_startup.py. Open it with a text editor and paste the following commands into the file:

import sys
import os
from pathlib import Path


# get directory of virtual environment
p_env = Path(sys.executable).parent

# directory which should contain all the DLLs
p_dlls = p_env / 'Library' / 'bin'

# effectively prepend this DLL directory to $PATH
# semi-colon used here as sep on Windows
os.environ['PATH'] = '{};{}'.format(p_dlls, os.environ['PATH'])

Everything in one-shot

If you feel lucky, you can try and copy-paste all install commands into a shell. Note that if one command fails, all subsequent commands will not be executed.

using conda:

conda create -n weldx -c conda-forge weldx
conda activate weldx
python -m ipykernel install --user --name weldx --display-name "Python (weldx)"
conda create -n jlab -c conda-forge jupyterlab k3d
conda activate jlab