docs/README.md

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# Apache SystemDS Documentation

The primary SystemDS documentation is written in markdown (*.md) and can be converted to HTML using
[Jekyll](http://jekyllrb.com).

The Documentation is separated into different parts by sub folders.

``` py
.
├── _layouts
│   ├── global.html # The Default content layout and html file.
├── _site # If run locally a _site folder is generated containing the compiled site.
├── _config.yml # The configuration for jekyll to construct the site.
├── Gemfile.yml # The dependency list for the documentation
├── index.md #  The main entry File
├── _layouts
│   ├── global.html
├── css # The style files folder
├── img # The Images folder
├── js  # The JavaScript folder
├── site # The different pages in the documentation
├── api # Contains autogenerated files. Don't touch manually
│   ├── java # The generated Java docs from source code.
│   ├── python # The generated Python docs from source code.
```

## Ubuntu Install

1. Install Ruby development environment [Jekyll on Ubuntu](https://jekyllrb.com/docs/installation/ubuntu/).
2. Install Jekyll inside the Ruby environment.

   - `gem install jekyll jekyll-redirect-from bundler pygments.rb`
   - To do this you might need to change permissions on folders `/var/lib/gems` and `/var/lib/gems/2.5.0`.
   - The Pygments package is optional, and does require sudo permissions.

3. Install python dependencies (Optionally).

   - `pip install Pygments`

4. Launch the Documentation locally

   - `jekyll serve -w`
   - This is done from the root of the gh-pages branch of the system.
   - The serving will per default be on localhost port 4000 [Link](http://localhost:4000)

### Update API

To update the API documentation run the `updateAPI.sh` file.
Note that you have to install both the Java and Python -doc dependencies.

## Mac Install

Jekyll (and optionally Pygments) can be installed on the Mac OS in the following manner.

```bash
brew install ruby
gem install jekyll
gem install jekyll-redirect-from
gem install bundler
brew install python
pip install Pygments
gem install pygments.rb
```

To generate SystemDS documentation in HTML, navigate to the ```docs``` folder, the root directory of the
documentation. From there, you can have Jekyll convert the markdown files to HTML. If you run in server mode,
Jekyll will serve up the generated documentation by default at <http://127.0.0.1:4000>. Modifications
to *.md files will be converted to HTML and can be viewed in a web browser.

```bash
jekyll serve -w
```