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Installing and Using LSST Science Pipelines as a Conda Package
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This page will guide you through installing the LSST Science Pipelines as a Conda package for use in `Anaconda or Miniconda <https://www.continuum.io/why-anaconda>`__.
Anaconda is a popular Python distribution and package ecosystem.
With this installation method you don't compile source code, or even need to have an existing Python installation.

.. note::

   This documentation does not cover the LSST Simulations software.
   See the `LSST Simulations installation documentation <https://confluence.lsstcorp.org/display/SIM/Catalogs+and+MAF>`_ instead.

If you have difficulty installing LSST software:

- review the :ref:`known installation issues for your platform <installation-issues>`.
- reach out on the `Support forum at community.lsst.org <https://community.lsst.org/c/support>`_.

1. Install Anaconda or Miniconda
================================

You might already have Anaconda or Miniconda as your main Python distribution.
If not, you can quickly get started by following Continuum's official installation instructions:

- `Install Anaconda <https://www.continuum.io/downloads>`__ if you want a complete, science-ready Python installation with minimal setup.
- Otherwise, `install the leaner Miniconda <http://conda.pydata.org/miniconda.html>`__ version and install packages as you need them.

.. warning:: 

   You need the Python 2 (e.g. Miniconda2) distribution. If you want to use the experimental Python 3 support, you should try our source installation. 

If you're new to Anaconda, Continuum's `30-minute test drive <http://conda.pydata.org/docs/test-drive.html>`_ tutorial will get you up-to-speed.

.. warning::

   Don't reuse the Miniconda you might have previously obtained from an :doc:`eups distrib <newinstall>`\ -based installation.
   Open a new shell and install Anaconda/Miniconda from scratch.

Upgrading conda
---------------

If you have an existing Anaconda or Miniconda installation, you'll want to make sure the :command:`conda` command itself is up to date:

.. code-block:: bash

   conda update conda

See the `Conda documentation for more information about installing and managing conda and Anaconda/Miniconda <http://conda.pydata.org/docs/using/using.html>`__.

2. Install Science Pipelines in a Conda Environment
===================================================

These commands will download and activate the LSST Science Pipelines in a new Conda environment:

.. code-block:: bash
   :linenos:

   conda config --add channels http://conda.lsst.codes/stack/0.13.0
   conda create --name lsst python=2
   source activate lsst
   conda install lsst-distrib
   source eups-setups.sh
   setup lsst_distrib
   
   You can ignore warnings about pre-link and post-link scripts being dangerous and deprecated. Sorry about that.

.. warning::

   Installing the LSST simulation tools (including MAF) requires pointing to a different Conda channel.
   See the `LSST Simulations installation documentation <https://confluence.lsstcorp.org/display/SIM/Catalogs+and+MAF>`_.

Here's what these commands are doing, line-by-line:

1. Tell :command:`conda` about the LSST channel for Conda packages.
2. Create a Conda environment called ``lsst`` with Python 2.7.
   You can change the environment's name to anything you like.
   Conda environments are recommended since they help keep the Python dependencies of your projects separate.
   See the `Conda documentation on environments for more information <http://conda.pydata.org/docs/using/envs.html>`__.
3. Activate the ``lsst`` environment (use your environment's name if you chose a different one).
   The :command:`activate` command is provided by Anaconda/Miniconda (e.g. at :file:`~/miniconda2/bin/activate`).
4. Install the full suite of LSST science software, including Science Pipelines (``lsst-distrib``).
5. Setup EUPS, LSST's package manager.
6. Setup LSST packages in your environment with EUPS (setting up ``lsst_distrib`` makes most packages available to you).

.. warning::

   If the install fails with an error, check that your shell does not have another EUPS Stack configured (try ``echo $EUPS_STACK``).
   Conda packaged EUPS will use existing values of ``EUPS_PATH`` and ``EUPS_DIR``.
   If they exist, unset them before installing or using Conda packages.

.. _conda-install-activate:

3. Activating Science Pipelines in a new Shell
==============================================

Whenever you open a new shell or terminal session, use these commands to re-activate your previously-installed Science Pipelines:

.. code-block:: bash
   :linenos:

   source activate lsst
   source eups-setups.sh
   setup lsst_distrib

These commands can also be used to switch from one Conda environment and LSST Science Pipelines installation to another.

.. _conda-install-test:

4. Testing Your Installation
============================

Once the LSST Science Pipelines are installed, you can verify that it works by :doc:`running a demo project <demo>`.
This demo processes a small amount of SDSS data.