src/main/python/README.md

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# Apache SystemDS

![Python Test](https://github.com/apache/systemds/workflows/Python%20Test/badge.svg)

This package provides a Pythonic interface for working with SystemDS.

SystemDS is a versatile system for the end-to-end data science lifecycle from data integration,
cleaning, and feature engineering, over efficient, local and distributed ML model training,
to deployment and serving.
To facilitate this, bindings from different languages and different system abstractions provide help for:

1. The different tasks of the data-science lifecycle, and
2. users with different expertise.

These high-level scripts are compiled into hybrid execution plans of local, in-memory CPU and GPU operations,
as well as distributed operations on Apache Spark. In contrast to existing systems - that either
provide homogeneous tensors or 2D Datasets - and in order to serve the entire
data science lifecycle, the underlying data model are DataTensors, i.e.,
tensors (multi-dimensional arrays) whose first dimension may have a heterogeneous and nested schema.

## Publishing Instructions

### Building SystemDS jar (with dependency jars)

The following steps have to be done for both the cases

- Build SystemDS with maven first `mvn package -P distribution`, with the working
  directory being `SYSTEMDS_ROOT` (Root directory of SystemDS)
- `cd` to this folder (basically `SYSTEMDS_ROOT/src/main/python`)

### Building python package

- Run `create_python_dist.py`

```bash
python3 create_python_dist.py
```

- now in the `./dist` directory there will exist the source distribution `systemds-VERSION.tar.gz`
  and the wheel distribution `systemds-VERSION-py3-none-any.whl`, with `VERSION` being the current version number

### Publishing package

If we want to build the package for uploading to the repository via `python3 -m twine upload dist/*`
  (will be automated in the future)

- Install twine with `pip install --upgrade twine`

- Follow the instructions from the [Guide](https://packaging.python.org/tutorials/packaging-projects/)
    1. Create an API-Token in the account (leave the page open or copy the token, it will only be shown once)
    2. Execute the command `python3 -m twine upload dist/*`
        - Optional: `pip install keyrings.alt`(use with caution!) if you get `UserWarning: No recommended backend was available.`
    3. Username is `__token__`
    4. Password is the created API-Token **with** `pypi-` prefix