Simplify install instructions

Issue #16

doc/install.rst

@@ -1,113 +1,83 @@
 Installation
 ============
 
-Before you can install pyCPA, you must set up Python 2.7 and all required python packages (`Step 1`_).
+Before you can install pyCPA, you must set up Python (`Prerequisites`_).
+If you already have a Python installation, you may directly proceed with `Quickstart`_.
+Alternatively, if you want to modify the pyCPA code, please consult `For Developers`_.
 
-In a second step, pyCPA will be installed in a manual procedure.
+A brief introduction in how to test your installation is provided in `Using pyCPA`_.
 
-The guide below explains both steps.
-If you have already set up a sophisticated Python environment, you may directly proceed with `Step 2`_.
 
-.. _Step 1: 
+.. _Prerequisites:
 
-Step 1: Setting up prerequisites
---------------------------------
+Prerequisites
+-------------
 
-In this step, we are going to install a compatible version of Python on your system along with additional Python packages
-required by pyCPA.
-Please note, that the preferred version is Python 2.7, but most parts of pyCPA are also compatible with Python 3.
+First of all, you need a basic Python (2.7 or 3.x) environment.
+As a Linux user, you most probably have Python already installed.
+On Windows, we recommend to use `Python(x,y) <https://python-xy.github.io/>`_, which includes a comprehensive set of scientific Python libraries and tools as well as related documentation.
+Python(x,y) comes with several interactive consoles (based on IPython), editors and applications.
+For your first hands-on experience, we recommend using ``Spyder`` as an IDE.
+You can also run a command prompt via the Python(x,y) icon on the Desktop and choosing ``IPython (sh)`` as an interactive console.
 
-* Required Python packages: setuptools, argparse, pygraphviz, matplotlib
-* Optional Python packages: numpy, simpy, xlrd
 
-Linux
-^^^^^
+.. _Quickstart:
 
-We assume, Linux users will be familiar with installing any packages from their distribution's repositories.
-Most likely, Python will already be installed on your system and if not it will typically be installed automatically (as a dependency) when installing the additional Python packages.
+Quickstart
+----------
 
-Before proceeding, you might want to check the status of your Python installation, i.e. what version is installed (if
-at all) and what Python packages are already available, using the following commands:
+The easiest way to install pyCPA is by using `pip <https://pypi.org/project/pip/>`_.
+For a system-wide installation of the current pyCPA version, you simply run the following command:
 
 .. code-block:: bash
-   
-   $ python --version
-   $ pydoc modules
 
-If you use Ubuntu/Debian, you can install missing packages using the following commands:
+   $ pip install https://bitbucket.org/pycpa/pycpa/get/master.zip
 
-.. code-block:: bash
-
-   $ sudo apt-get install python-setuptools python-argparse python-pygraphviz python-matplotlib python-numpy python-simpy python-xlrd
-
-If your distribution does not provide similar packages, you can use ``pip`` to install additional python packages.
+Alternatively, e.g. if you do not have admin privileges, you can install pyCPA for the current user:
 
 .. code-block:: bash
 
-   $ pip install simpy
-
-Windows
-^^^^^^^
-We recommend to use `Python(x,y) <https://python-xy.github.io/>`_, which includes a comprehensive set of scientific
-Python libraries and tools as well as related documentation.
-Most of the required Python modules such as matplotlib are already included,
-but some (SimPy) have to be installed by hand if required.
-It is recommended to uninstall any other Python distribution before installing Python(x,y).
+   $ pip install --user https://bitbucket.org/pycpa/pycpa/get/master.zip
 
-In order to safe disk space, you may choose the recommended setting during installation and additionally check xlrd and pygraphviz.
-Python(x,y) comes with several interactive consoles (based on IPython), editors and applications.
-For your first hands-on experience, we recommend using ``Spyder`` as an IDE.
-You can also run a command prompt via the Python(x,y) icon on the Desktop and choosing ``IPython (sh)`` as an interactive
-console.
 
-You can install missing packages using the recommended installer for python packages, ``pip``, from the command prompt. ``pip`` is included in Python(x,y).
-
-.. code-block:: bash
+.. _For Developers:
 
-   $ python -m pip install simpy
+For Developers
+--------------
 
-For a detailed documentation regarding package installation you may consult the `official website <https://packaging.python.org/tutorials/installing-packages/>`_.
+pyCPA has the following dependencies:
 
-.. _Step 2: 
-
-Step 2: Downloading and setting up pyCPA
-----------------------------------------
-
-For downloading the pyCPA source code, you have two options:
-
-A. **Easisest**: Download and extract the latest pyCPA release from `Bitbucket <https://bitbucket.org/pycpa/pycpa/downloads/>`_.
+* Required Python packages: setuptools, argparse, pygraphviz, matplotlib
+* Optional Python packages: numpy, simpy, xlrd
 
-B. For experts: If you are familiar with git, you can alternatively clone the repository using `git <https://git-scm.com/>`_, e.g. by running the following command:
+Before proceeding, you might want to check the status of your Python installation, i.e. what version is installed (if
+at all) and what Python packages are already available, using the following commands:
 
-   .. code-block:: bash
+.. code-block:: bash
+   
+   $ python --version
+   $ pydoc modules
 
-      $ git clone https://bitbucket.org/pycpa/pycpa/
+For downloading the pyCPA source code, you simply create a clone from the git `git <https://git-scm.com/>`_ repository, e.g. by running the following command:
 
-Depending on how you want to use pyCPA, there are two ways of making pyCPA available to your python installation:
+.. code-block:: bash
 
-A. **Easiest**: Install pyCPA into your python installation using the command prompt from the pyCPA directory.
-   This is for people who just want to use pyCPA as it comes.
+   $ git clone https://bitbucket.org/pycpa/pycpa/
 
-   .. code-block:: bash
 
-      $ python setup.py install
+From within the pyCPA repository, execute the following command to install pyCPA in editable mode (i.e. changes to the
+source code do not require re-installation to be effective):
 
-B. For experts: Leave pyCPA where it is and tell Python to use the module in-place.
-   This is for people who want to modify pyCPA or use different versions in parallel.
-   You achieve this by setting the PYTHONPATH variable to the pyCPA directory.
-   For command line users, this is done as follows:
+.. code-block:: bash
 
-   .. code-block:: bash
+   $ pip install --user -e .
 
-      $ export PYTHONPATH="/path/to/pyCPA:$PYTHONPATH"
 
-   Note that you must *NOT* specify the subdirectory ``pycpa`` within the pyCPA directory.
-   If you prefer using an IDE, please refer to `Using an IDE: PyDev`_.
 
-.. _Step 3: 
+.. _Using pyCPA:
 
-Step 3: Testing and using pyCPA
--------------------------------
+Testing and using pyCPA
+-----------------------
 
 Congratulations, you have installed pyCPA!
 
@@ -135,7 +105,7 @@ Using an IDE: PyDev
 
 You may also use Eclipse with PyDev as IDE, which can be installed by the following steps:
 
-1. Make sure that you have installed Python 2.7 *BEFORE* you install Eclipse.
+1. Make sure that you have installed Python *BEFORE* you install Eclipse.
 2. Download from `<http://www.eclipse.org/downloads/eclipse-packages/>`_ the current Eclipse release for Windows 32 bit (!). Extract the zip-file, execute ``eclipse.exe`` and follow the installation instructions.
 3. Open Eclipse and specify a workspace. If you open a workspace for the first time, you will have to close the Welcome tab, before proceeding to your workspace.
 4. Select the menu item ``Help –> Install New Software``, search for the site `<http://pydev.org/updates>`_. Select and install the item “PyDev” which will be displayed in the list of available software.