Trident
=======

Trident is a python-based package extending yt for generating synthetic
absorption-line spectra of hydrodynamical datasets.  For more information
about Trident and yt, please visit the websites or look at the code repository:

http://trident-project.org

http://bitbucket.org/trident-project/trident

http://yt-project.org


Installation
------------

The Trident source is most easily installed using pip.  But you can only
do this once you've installed yt and its dependencies.  If you already have
the dev version of yt installed, then skip to step 2.  


Step 1: Install yt  
^^^^^^^^^^^^^^^^^^

There are several methods for doing this all discussed in detail in the yt 
docs here: http://yt-project.org/docs/dev/installing.html
Note that Trident currently requires the development branch of yt to work
properly.

If you're just starting out, we recommend the anaconda method as the least
work for new users to get yt installed as described here (be sure to get 
the development version of yt):
http://yt-project.org/docs/dev/installing.html#installing-yt-using-anaconda


Step 2: Install Trident
^^^^^^^^^^^^^^^^^^^^^^^

You can install Trident using pip::

    $ pip install trident


Step 3: Get Ionization Table
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

In order to calculate the ionization fractions for various ions from 
density, temperature, metallicity, and redshift fields, you will need 
an ionization table data file and a configuration file.  The first time 
you import Trident into Python, the code will attempt to automatically 
set this all up for you with a series of interactive prompts.  If this works
for you, then you're done and you can skip to step 4::

    $ python
    >>> import trident

Alternatively, you can set this up manually by downloading/unzipping one of the 
files at http://trident-project.org/data/ion_table .  You can store this
file wherever you desire, just assure the config file in your ``$HOME/.trident``
directory points to it.  As an example, if you placed the ``hm2012_hr.h5`` ion
table file in your ``~/.trident`` directory, the contents of 
``$HOME/.trident/config`` would be::

    [Trident]
    ion_table_dir = ~/.trident
    ion_table_file = hm2012_hr.h5

To assure this is all working after you have set it up.  Try to load Trident.
If you can do that, then you're ready to move to Step 4::

    $ python
    >>> import trident

Step 4: Science!
^^^^^^^^^^^^^^^^

You're now ready to use Trident.  Please refer to the documentation for how
to use it with your data or with one of our sample datasets.


Documentation and Mailing List
------------------------------

To view our documentation, please visit:

http://trident.readthedocs.org


For questions, comments, and announcements, please join our low-volume 
mailing list:

https://groups.google.com/forum/#!forum/trident-project-users
