Gamma-ray Data Tools - Core Components

The Gamma-ray Data Tools (GDT) is centralized toolkit for hard X-ray and gamma-ray astrophysics data analysis, with a focus on providing a uniform interface to the data provided by several different missions and instruments.

The GDT Core Package (astro-gdt) contains the core components of the GDT that can be utilized for various instruments and is a generalized version of the Fermi GBM Data Tools. Individual mission or instrument packages can be developed using astro-gdt and released under the gdt.missions namespace (see astro-gdt-fermi as an example).

The full documentation can be found here.

Normal Installation

If you don't plan to contribute code to the project, the recommended install method is installing from PyPI using:

pip install astro-gdt
gdt-data init

The gdt-data init is required to initialize the library after installation.

Contributing to the GDT

Community contributions to the GDT are welcome and make the GDT a better toolkit for everyone to use. There are various types of contributions. These include:

• Bug fixes
• New features
• Documentation improvements
• API improvements
• New mission packages

For each contribution, we consider it best practice to first open an issue (with an appropriate label). This may be as simple as notifying us (and other users!) that there is a bug. Perhaps you also have a proposed solution to fixing the issue. If so, then you can outline your proposed fix when you open the issue, and we will give you feedback about whether we think that would be a useful and appropriate fix.

Simple typographical fixes and clarifications made in the documentation do not require the creation of an issue.

If your proposed modifications are significant (e.g. sizable document change, API improvements, new feature), we highly recommend that you detail the propose change in the issue and wait for feedback. This is to save you precious time in the event that we decide not to accept your proposed solution. Often the proposed solution can break functionality elsewhere or can be simplified, and we would like to have a chance to provide useful feedback before you begin coding. Waiting for feedback is not a requirement, but merely reduces the chance of additional changes prior to having your pull request accepted.

If you are submitting code modifications, we require that you create a unit test to confirm expected operation of the code if those modifications aren't already covered by an existing unit test.

The usual sequence of events are:

1. Create an issue describing the proposed changes.
2. Waiting for feedback if desired.
3. Create a fork from main branch.
4. Use your fork to add your changes to the code base.
5. Create unit tests showing that your changes work as intended.
6. Create Pull Request with a comment explaining how it closes the issue you created.

Setting up a development environment

If you do want to contribute code to this project (and astro-gdt), you can use the following commands to quickly setup a development environment:

mkdir gdt-devel
cd gdt-devel
python -m venv venv
. venv/bin/activate
pip install --upgrade pip setuptools wheel
git clone git@github.com:USRA-STI/gdt-core.git
pip install -e gdt-core/
gdt-data init
pip install -r gdt-core/requirements.txt

This should result in git-devel having the following directory structure:

.
├── venv
└── gdt-core

with gdt-core installed in the virtual environment named venv.

Writing Extensions using Namespace Packaging

Gamma-ray Data Tools encourages missions to write extensions using namespace packages. Please use our Fermi extension as an example of how we expect other missions to contribute extensions to the Gamma-ray Data Tools.

The extension package should contain a directory 'gdt' with a subdirectory 'missions' which will hold the extension code in a package directory named after the mission.

For example, GDT-Fermi has the following directory layout:

.
├── config
├── dist
├── docs
├── src
│   └── gdt
│      └── missions
│          └── fermi
│              ├── gbm
│              │   └── __init__.py
│              ├── lat
│              │   └── __init__.py
│              └── __init__.py
└── tests
  └── missions
      └── fermi

Since GDT-Fermi uses namespace packaging, both src/gdt and src/gdt/missions do not contain a file named __init__.py. This is because they are Namespace packages.

Notice that directory src/gdt/mission/fermi and its subdirectories contains an __init__.py file signalling to Python that those directories are regular packages.

You can learn more about Namespace packages by reading PEP-420.

Helping with Documentation

You can contribute additions and changes to the documentation. In order to use sphinx to compile the documentation source files, we recommend that you install the packages contained within requirments.txt.

To compile the documentation, use the following commands:

cd gdt-core/docs
make html