{"id":6699,"library":"lalsuite","title":"LIGO Scientific Collaboration Algorithm Library - minimal Python package","description":"LALSuite is the LIGO Scientific Collaboration Algorithm Library for gravitational-wave analysis. Its primary purpose is searching for and characterizing astrophysical signals in gravitational-wave time series data, particularly data from ground-based detectors such as LIGO and Virgo. This Python package provides a standalone, dependency-free binary distribution of the libraries and Python modules in LALSuite for Linux and macOS. Current version is 7.26.4, with underlying C components (like LAL, LALSimulation) also updated regularly.","status":"active","version":"7.26.4","language":"en","source_language":"en","source_url":"https://git.ligo.org/lscsoft/lalsuite.git","tags":["astronomy","physics","gravitational waves","LIGO","Virgo","data analysis","scientific computing"],"install":[{"cmd":"pip install lalsuite","lang":"bash","label":"Install core package"},{"cmd":"pip install lalsuite[lalinference]","lang":"bash","label":"Install with LALInference dependencies"},{"cmd":"pip install lalsuite[lalpulsar]","lang":"bash","label":"Install with LALPulsar dependencies"}],"dependencies":[{"reason":"Pulled in by `lalsuite[lalinference]` for gravitational-wave data finding.","package":"gwdatafind","optional":true},{"reason":"Pulled in by `lalsuite[lalinference]` for gravitational-wave Python utilities.","package":"gwpy","optional":true},{"reason":"Pulled in by `lalsuite[lalpulsar]` to provide ephemeris files. (Included in main package until LALSuite 7.15).","package":"solar_system_ephemerides","optional":true},{"reason":"Pulled in by `lalsuite[test]` for running tests.","package":"pytest","optional":true}],"imports":[{"note":"Top-level import for core LAL functionalities.","symbol":"lal","correct":"import lal"},{"note":"Top-level import for LALSimulation functionalities, e.g., waveform generation.","symbol":"lalsimulation","correct":"import lalsimulation"},{"note":"Specific import for GPS time utilities.","symbol":"GPSTime","correct":"from lal import GPSTime"}],"quickstart":{"code":"from lal import GPSTime\n\n# Create a GPSTime object representing a specific GPS second\ntry:\n    gps_time = GPSTime(1126259642.4) # Example GPS time\n    print(f\"Created GPSTime object: {gps_time}\")\n    print(f\"Year of GPS time: {gps_time.gps_year}\")\n    print(f\"Fractional seconds: {gps_time.gps_fraction}\")\nexcept Exception as e:\n    print(f\"An error occurred: {e}\")\n    print(\"Note: LALSuite often requires specific environment setups or data files for full functionality.\")\n\n# More advanced usage often involves lalsimulation for waveform generation\n# import lalsimulation\n# hp, hc = lalsimulation.SimIMRSpinAlignedEOBWaveform(...) # Example, not runnable without parameters\n","lang":"python","description":"This quickstart demonstrates how to import the `GPSTime` class from the `lal` module and instantiate a GPS time object. LALSuite offers a wide range of functionalities for gravitational-wave data analysis, including signal generation (e.g., via `lalsimulation`), data manipulation, and parameter estimation. Further examples would involve specific physics computations."},"warnings":[{"fix":"Use a Linux or macOS environment, or leverage WSL/virtualization on Windows.","message":"The `lalsuite` Python package is only officially supported on Linux and macOS. Windows users typically need to use Windows Subsystem for Linux (WSL) or a virtual machine to run it.","severity":"gotcha","affected_versions":"All versions"},{"fix":"Download the necessary data files from the specified sources (Zenodo/GitLab repositories) and set the `LAL_DATA_PATH` environment variable to their location.","message":"Some advanced compact binary coalescence waveform models require additional data files (e.g., for reduced order models). These files need to be downloaded separately (from Zenodo or specific Git repositories like `lalsuite-waveform-data` for versions >= 7.25, or `lalsuite-extra` for earlier versions). The `LAL_DATA_PATH` environment variable must then be set to point to the downloaded directory.","severity":"gotcha","affected_versions":"All versions requiring specific waveform data"},{"fix":"Consult the LALSuite documentation and C-language specification (LAL Spec) to understand the underlying C API conventions, especially regarding function arguments and error reporting.","message":"The Python interface of LALSuite wraps underlying C libraries. As a result, users might encounter C-level concepts and conventions, such as `LALStatus` pointers for error handling in 'LAL' functions or distinct error reporting in 'XLAL' functions. This can differ from typical Pythonic error handling and requires familiarity with LAL C-style conventions.","severity":"gotcha","affected_versions":"All versions"}],"env_vars":null,"last_verified":"2026-04-15T00:00:00.000Z","next_check":"2026-07-14T00:00:00.000Z","problems":[]}