LISA Glitch

LISA Glitch is a Python package that generates realistic instrumental artefacts for the LISA (Laser Interferometer Space Antenna) gravitational wave detector. The package includes:

Features

Glitch Generation (glitch submodule)

• LPF-based models: Realistic glitches based on LISA Pathfinder data
• Mathematical models: Simple analytical glitch shapes
• Machine learning: Neural network-based parameter distributions
• Compatibility with lisainstrument: Ability to write glitch files to be read by lisainstrument

Gap Mask Generation (gap submodule)

• Planned gaps: Regular maintenance and calibration windows
• Unplanned gaps: Stochastic outages and communication losses
• Configurable rates: User-defined gap frequencies and durations
• Construction of binary mask: Create binary masks for gap regions
• HDF5 I/O: Save and load gap configurations
• Quality flags: Generate data quality indicators (0 for valid data, 1 for missing data)

Online Documentation

Full documentation for the LISA Glitch package is available at: https://lisa-simulation.pages.in2p3.fr/glitch

Package Structure

lisaglitch/
├── glitch/              # Glitch generation (former lisaglitch)
│   ├── base.py          # Base glitch classes
│   ├── lpf.py           # LPF-based models
│   ├── math.py          # Mathematical models
│   ├── read.py          # File I/O utilities
│   └── ...
└── gap/                 # Gap mask generation (former lisagap)
    ├── __init__.py
    └── gap_mask_generator.py

Quick Start

from lisaglitch import ShapeletGlitch, GapMaskGenerator
import numpy as np

# Generate time array
t = np.arange(0, 60*60, 0.25)  # 1 hour at 4 Hz

# Create a glitch injected at test mass inteferometer 12 [tmi_12]
# with some amlitude [level] and damping time [beta] injected at the
# 1800 second mark

glitch = ShapeletGlitch(level=1e-10, beta=100, inj_point="tm_12", t_inj=1800)
signal = glitch.compute_signal(t)

# Create gap mask
# Define gap configuration with planned and unplanned gaps
# treated as dictionary of dictionaries defining rates and durations.
gap_config = {
    "planned": {"maintenance": {"rate_per_year": 52, "duration_hr": 1}},
    "unplanned": {"outage": {"rate_per_year": 10, "duration_hr": 0.5}}
}

# Initialise class with time array, time step, and gap definitions
# treating missing data with NaNs.
gap_gen = GapMaskGenerator(t, treat_as_nans=True, gap_definitions=gap_config)
mask = gap_gen.generate_mask(include_planned=True, include_unplanned=True)

# Apply gaps to signal
masked_signal = signal * mask

Installation

For Users

Install the latest release from PyPI:

pip install lisaglitch

For Developers

This project uses Poetry for dependency management and packaging. Poetry automatically creates and manages virtual environments, eliminating the need for manual virtualenv or conda environment management.

⚠️ Important: This project requires Poetry 2.0 or higher. If you have an older version, please upgrade.

Installation Steps

Step 1: Install Poetry (one-time setup)

Poetry works on Windows, macOS, and Linux. Choose your method:

Option A: Official installer (recommended)

curl -sSL https://install.python-poetry.org | python3 -

Option B: Using pip (if you already have Python)

pip install poetry

Option C: Using package managers

# macOS with Homebrew
brew install poetry

# Ubuntu/Debian
sudo apt install python3-poetry

# Windows with Chocolatey
choco install poetry

Verification: Check Poetry installation

poetry --version  # Must show Poetry 2.0 or higher

Step 2: Clone and Setup the Project

# Clone the repository
git clone git@gitlab.in2p3.fr:lisa-simulation/glitch.git
cd glitch

# Install all dependencies including development tools
poetry install --with dev,test,doc

Step 3: Activate the Environment

Poetry provides two ways to work with your environment:

Option A: Activate shell (similar to conda/virtualenv)

# Enter Poetry shell (recommended for interactive work)
source $(poetry env info --path)/bin/activate

# Your prompt will change to show: (lisaglitch-py3.12)
# Now you can use python, pytest, etc. directly
python -c "import lisaglitch; print('✅ Ready to go!')"

Option B: Run commands through Poetry (no activation needed)

# Run Python scripts
poetry run python your_script.py

# Run tests
poetry run pytest

# Install new packages
poetry add numpy matplotlib  # Runtime dependencies
poetry add --group dev black  # Development dependencies

[Development Purposes] Building Documentation Locally

For developers and contributors working on branches: The online documentation at https://lisa-simulation.pages.in2p3.fr/glitch only reflects the main branch. If you're working on a development branch or want to view documentation with your local changes, build it locally:

make -C docs html

The built documentation will be available at:

• File path: docs/_build/html/index.html (open directly in browser)
• Local server: http://localhost:8000 (if using the server option)

This is especially useful when:

• Working on documentation updates
• Testing new features before merging to main
• Reviewing documentation changes in pull/merge requests

Documentation Structure

• Getting started: Basic usage examples
• Tutorials: Interactive Jupyter notebooks on gaps and glitches
• Glitch Documentation: Detailed documentation on glitches
• API Reference: Complete class and method documentation

GitLab Pages Deployment

Documentation is automatically built and deployed to GitLab Pages on tagged releases. The CI/CD pipeline:

1. Build Stage: Generates HTML documentation using Sphinx
2. Deploy Stage: Publishes to GitLab Pages (on tags only)

The live documentation is available at: https://lisa-simulation.pages.in2p3.fr/glitch

Pushing Changes to Branches

When pushing changes to branches, ensure you follow the project's development workflow. This includes running quality checks and tests before pushing to avoid CI failures.

Automated Quality Checks with VSCode

Developers can use VSCode tasks to automate the quality check process, mirroring the CI/CD pipeline:

1. Open Command Palette: Cmd + Shift + P (macOS) or Ctrl + Shift + P (Windows/Linux)
2. Select Task: Choose "Run Task" from the dropdown
3. Choose Quality Check: Select from available tasks:
   • Run Mypy - Type checking
   • Check Black Formatting - Code formatting
   • Run Pre-Commit Hooks - Comprehensive linting
   • Run Tests with Coverage - Unit tests with coverage report
   • Full CI Pipeline (Without PyPI publish) - Complete validation suite

Manual Quality Checks using console

You can run them manually with Poetry:

# Type checking
poetry run mypy lisaglitch

# Code quality
poetry run pylint lisaglitch

# Unit tests
poetry run python -m pytest tests/

# Pre-commit hooks (formatting, linting, etc.)
poetry run pre-commit run --all-files

./build_docs.sh  # Build documentation

Contributing

Report an issue

We use the issue-tracking management system associated with the project provided by Gitlab. If you want to report a bug or request a feature, open an issue at https://gitlab.in2p3.fr/lisa-simulation/glitch/-/issues. You may also thumb-up or comment on existing issues.

Workflow

The project's development workflow is based on the issue-tracking system provided by Gitlab, as well as peer-reviewed merge requests.

Issues are solved by creating branches and opening merge requests. Only the assignee of the related issue and merge request can push commits on the branch. Once all the changes have been pushed, the "draft" specifier on the merge request is removed, and the merge request is assigned to a reviewer. He can push new changes to the branch, or request changes to the original author by re-assigning the merge request to them. When the merge request is accepted, the branch is merged onto master, deleted, and the associated issue is closed.

Code Quality and Testing

We enforce PEP 8 (Style Guide for Python Code) with Pylint syntax checking, static type checking with mypy, and correction of the code using the pytest testing framework. All are implemented in the continuous integration system.

Acknowledgements

The implementation of the flow, which is used for learning and sampling from the LISA Pathfinder distribution, is heavily based on the neural spline flows implementation provided by the authors: nsflows and also its orignal implentation: nsf. With some simplifications borrowed from here and here.

Use policy

The project is distributed under the 3-Clause BSD open-source license to foster open science in our community and share common tools. Please keep in mind that developing and maintaining such a tool takes time and effort. Therefore, we kindly ask you to

• Cite the DOI (see badge above) in any publication
• Acknowledge the authors (below)
• Acknowledge the LISA Simulation Expert Group in any publication

Do not hesitate to send an email to the authors for support. We always appreciate being associated with research projects.

Contact

• Jean-Baptiste Bayle (j2b.bayle@gmail.com)
• Ollie Burke (ollie.burke@glasgow.ac.uk)
• Eleonora Castelli (eleonora.castelli@nasa.gov)
• Natalia Korsakova (korsakova@apc.in2p3.fr)