Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

[0.3.0] - 2025-12-19

[library] CLI commands: colliderml download for downloading HuggingFace datasets with local caching, colliderml list-configs for discovering available configurations.
[library] Polars-based data loader with lazy/eager loading support and structured configuration (YAML/dict).
[library] Physics utilities: pileup subsampling, decay-chain traversal with primary ancestor assignment, calorimeter calibration with region-specific scaling factors.
[library] Flattening helpers to explode nested Parquet structures into pandas DataFrames for analysis.
[library] Visualization utilities: coordinate transformations (eta, r), binned energy profile plotting.
[library] Download timing benchmarks integrated into CI/CD.
[docs] Reference exploration notebook demonstrating loader, physics utilities, and visualization.

[library] Data loading now uses local Parquet cache populated by CLI, not direct HuggingFace streaming.
[library] Exploded/flattened data structures now return pandas DataFrames for downstream analysis.
[library] Physics constants (calorimeter calibration factors) centralized in colliderml.physics.constants.

[library] Decay traversal now correctly identifies root particles by broken parent links, ignoring the primary flag.
[library] Pileup subsampling now correctly filters tracker hits and calorimeter contributions by particle ID.
[library] Calorimeter calibration now handles both region names and raw detector IDs.

[dataset] Datasets now hosted on HuggingFace Hub for easier access and distribution.
[dataset] Support for standard HuggingFace datasets library for data loading.
[docs] Interactive dataset configurator with dynamic channel discovery from HuggingFace API.
[docs] Updated documentation site with HuggingFace integration examples.

[dataset] Migrated from NERSC manifest-based distribution to HuggingFace datasets.
[dataset] Data now stored in Parquet format with improved compression and accessibility.
[docs] Simplified data access workflow using load_dataset() instead of custom CLI.

[dataset] Initial release of ColliderML dataset with ttbar and ggf physics processes.
[dataset] Four detector hierarchy levels: particles, tracker_hits, calo_hits, and tracks.
[dataset] Approximately 100,000 simulated events per process with no pileup (pu0).
[library] Initial colliderml Python library with data access utilities.
[docs] Documentation website with VitePress framework.
[docs] Dataset configuration modal for exploring available data.

Unreleased changes should be added under a ## [Unreleased] header above with entries marked as [dataset], [library], or [docs].