A library for GALFIT
GALFIT, a well-established two-dimensional image fitting algorithm, as outlined in the work by Peng et al. (2002, AJ, 124, 266), serves as the basis for precise astronomical image surface brightness analysis. In pursuit of optimizing the utilization of GALFIT, GALFITools emerges as an collection of Python routines. These routines enhances the input and output parsing associated with GALFIT.
GALFITools extends its utility through an array of functionalities, including the facilitation of mask creation, star selection for PSFs, generation of multiple initial parameters, simulate galaxy images, multigaussian expansion (MGE) fitting, as well as computation of sky background and other pertinent photometric variables.
The python libraries required are:
- numpy
- astropy
- scipy
- matplotlib
- mgefit
Install GALFIT if you haven't done so. Make sure that GALFIT can run in any path in your terminal.
Optionally, the establishment of a virtual environment can be considered.
The latest release of GALFITools can be downloaded and subsequently installed via one of the following methods:
cd GALFITools pip install .
or
cd GALFITools python setup.py install
Alternatively, you can install it via pip:
pip install GALFITools
Here is tutorial for the installation of GALFITools:
In conjunction with the installation, a compilation of pertinent shell commands will be incorporated. Subsequently, a comprehensive evaluation of GALFITools' performance can be conducted through automated tests using the following procedure:
To run the tests locally, install and invoke tox:
pip install tox
run the tests:
tox
Once installed, you can test galfitools using any of the commands in the console.
In the example below, getReComp is used with the output GALFIT file galfit.01 to calculate the effective radius for a composite model consisting of three Sersic components:
❯ getReComp galfit.01 GALFITools: a library for GALFIT Version: 1.14.1 webpage: https://github.com/canorve/GALFITools number of model components: 3 Using a theta value of : 14.13 degrees Total Magnitude of the galaxy: 9.79 Surface brightness at radius of 50% of light (μr): 21.15 mag/'' Mean Surface Brightness at effective radius (<μ>e): 20.27 mag/'' The radius at 50% of light is 199.64 pixels or 49.91 "
For comprehensive insights into GALFITools' repertoire of routines and their optimal deployment, it is recommended to consult the provided documentation on usage, accessible via the following link:
This comprehensive resource elaborates on the practical implementation of each individual routine.
Video Tutorials:
Turn on English subtitles.
Here is a tutorial video for galaxy NGC720 using GALFITools:
Here is another for galaxy NGC1198 using GALFITools:
Here I model the barred spiral galaxy PGC 34232 with GALFITools v1.11.0:
For the customization of these functions to align with your specific scripting requirements, the API documentation serves as an indispensable resource. The detailed instructions for utilizing these functions within your own scripts can be found here:
Check the CODE OF CONDUCT
To acknowledge the utility of GALFITools in your research, we kindly request that you cite it as follows:
Añorve, C. (2024). canorve/GALFITools: GALFITools v1.7.7 (v1.7.7). Zenodo. https://doi.org/10.5281/zenodo.11206403
cite all versions using the DOI: https://doi.org/10.5281/zenodo.8216472
Check EllipSect to create surface brightness profiles from GALFIT output and estimate other photometric parameters:
For further capabilities and valuable extensions pertaining to GALFIT output, such as the generation of surface brightness profiles and estimation of other photometric parameters, we invite you to explore the EllipSect tool:
Should any questions or innovative suggestions arise, we encourage you to reach out via email to canorve [at] gmail [dot] com or initiate a discussion by opening an issue. Your input is invaluable in fostering the continual refinement of GALFITools, for the betterment of the GALFIT community and beyond.
The codebase of GALFITools is governed by the terms of the MIT license.
This project has been set up using PyScaffold 4.2.1. For details and usage information on PyScaffold see https://pyscaffold.org/.