2DFFT Utilities

.. todo::

        - Clean up this README
        - Rename overlay.py to spiral_overlay.py
        - Add overlay.py instructions.
        - Change tabs to 4 spaces everywhere.

2dfft_utils is a collection of utilities that make processing 2DFFT pitch angle data for spiral galaxies a snap.

Dependencies

All scripts are currently standalone (so that you can pick and choose which to use), so users are encouraged to look at individual script dependencies.

If you plan on using all the scripts, you will need the following:

• Python (tested only on 2.7)
• Numpy
• Matplotlib
• IRAF
• PyRAF
• AstroPy
• 2DFFT

Optional dependencies:

• Ghostscript
• ImageMagick

Users new to Python, IRAF, and/or AstroPy are encouraged to make use of an installation package such as Ureka, which includes all main dependencies (other than 2DFFT).

Background

The tightness of arms in the disks of spiral galaxies (otherwise known as pitch angle) can be measured using the 2DFFT (2-Dimensional Fast Fourier Transform) package described in Davis et al. 2012

Taking a large number of images through the pitch angle measurement process can be very time-intensive, so we put together a number of (mostly) Python scripts to automate as many of these tasks as possible. We hope to make these utilities (which currently exist as standalone scripts) into a cohesive package in the near future.

User guide

Please see the :ref:`user-guide` in the docs folder for detailed instructions on how to get started.

Note

Instructions have been tested only in Ubuntu and Mac. Instructions may need to be modified.

Note

This guide was written for use with simulation data where galaxy images are already face-on, and currently includes no scripts for de-projecting.

Observational data in FITS images that have been deprojected will work as intended.