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Install SystemDS
================

SystemDS can be installed via `pip` or installed from source.


Pip
---

Installation is quite simple with `pip`, just execute the following command::

  pip install systemds

SystemDS is a java-project, the `pip` package contains all the necessary `jars`,
but you will need java version 11 installed. Do not use an older or newer
version of java, because SystemDS is non compatible with other java versions.

Check the output of ``java -version``. The output should look similar to::

  openjdk version "11.0.18" 2023-01-17
  OpenJDK Runtime Environment (build 11.0.18+10-post-Ubuntu-0ubuntu122.04)
  OpenJDK 64-Bit Server VM (build 11.0.18+10-post-Ubuntu-0ubuntu122.04, mixed mode, sharing)

The important part is in the first line ``openjdk version "11.xx"``,
please make sure this is the case.


Source
------

To Install from source involves multiple steps.

Install Dependencies 

- `Maven <https://maven.apache.org/>`_ 
- `Python 3.6+ <https://www.python.org/downloads/>`_ and
- `OpenJDK 11.xxx Java <https://openjdk.java.net/install/>`_

Once installed you please verify your version numbers. 
Additionally you have to install a few python packages.
We suggest to create a new virtual environment using virtual env. 
All commands are run inside src/main/python/.
We assume that in the following scripts python==python3

  python -m venv python_venv 

Now, we activate the environment.

  source python_venv/bin/activate 

In case of using Linux. For Windows PowerShell use:

  Set-ExecutionPolicy -ExecutionPolicy Bypass -Scope Process -Force
  python_venv/Scripts/Activate.ps1 

Note depending on your installation you might need to use pip3 instead of pip::

  pip install numpy py4j wheel requests

Then to build the system you do the following

- Clone the Git Repository: https://github.com/apache/systemds.git
- Open an terminal at the root of the repository.
- Package the Java code using the ``mvn clean package -P distribution`` command
- ``cd src/main/python`` to point at the root of the SystemDS Python library.
- Build the Python API ``python create_python_dist.py``
- Install with ``pip install .``

After this you are ready to go.