PurpleAir
The R client for PurpleAir sensors keeps finding its time-averaging was wrong.
Comparison · Analytics
lstar vs regfusionr
A side-by-side editorial comparison of lstar and regfusionr — release velocity, themes, recent moves, and the top alternatives to consider.
lstar vs regfusionr: at a glance
What is lstar?
A single-cell data store commits to Zarr v3 and range-readable hosting across four language surfaces
lstar stores single-cell data behind one C++ core with Python, R and JS/WASM bindings, and ships a browser viewer that reads the store directly. Zarr v3 is now the default on-disk format across all four surfaces, with zstd compression and sharding that packs many chunks into fewer objects. Viewer stores are compressed per field and resolved at chunk granularity, so a hosted viewer fetches only what it displays. The tag stream carries both lstar and lstar-sc releases.
What is regfusionr?
Registration fusion mapping goes bidirectional, and a vertex-indexing bug that silently returned wrong coordinates is fixed
regfusionr maps coordinates between volumetric brain templates (MNI152, Colin27) and the fsaverage surface. After four dormant years it returned in July 2026 with a release that fixes a coordinate-indexing bug, unblocks a previously disabled function, and completes the template-by-method matrix so all four combinations answer point queries. It also breaks compatibility by switching to the standard FREESURFER_HOME environment variable.
lstar vs regfusionr: editorial side-by-side
lstar
5.0ANALYTICS
A single-cell data store commits to Zarr v3 and range-readable hosting across four language surfaces
◆ Current state
lstar stores single-cell data behind one C++ core with Python, R and JS/WASM bindings, and ships a browser viewer that reads the store directly. Zarr v3 is now the default on-disk format across all four surfaces, with zstd compression and sharding that packs many chunks into fewer objects. Viewer stores are compressed per field and resolved at chunk granularity, so a hosted viewer fetches only what it displays. The tag stream carries both lstar and lstar-sc releases.
◆ Where it's heading
The through-line is making a hosted store cheap to read. Sharding addresses the file-per-chunk explosion that makes many-chunk arrays awkward to host; per-field compression with chunk-granular resolution means colouring an embedding by one gene fetches one column rather than an array. The 0.2.x patches are the cost of maintaining four surfaces at once — a WASM heap crash that only browsers exercise, and a count-basis orientation defect where all three surfaces normalized in memory and none owned the on-disk layout.
◆ Prediction
The orientation bug's root cause — no surface owning the on-disk representation while all three normalized in memory — is the kind of gap that usually produces a validation or ownership change rather than another point fix.
regfusionr
3.8ANALYTICS
Registration fusion mapping goes bidirectional, and a vertex-indexing bug that silently returned wrong coordinates is fixed
◆ Current state
regfusionr maps coordinates between volumetric brain templates (MNI152, Colin27) and the fsaverage surface. After four dormant years it returned in July 2026 with a release that fixes a coordinate-indexing bug, unblocks a previously disabled function, and completes the template-by-method matrix so all four combinations answer point queries. It also breaks compatibility by switching to the standard FREESURFER_HOME environment variable.
◆ Where it's heading
The package moved from a partial implementation to a complete one in a single release. Before this, vol_coords_to_fsaverage returned coordinates indexed by query position rather than by vertex index — results that looked plausible and were wrong — and fsaverage_to_vol was guarded behind a stop(). Both are now resolved, and the new Colin27 and MNI152 convenience functions make the mapping bidirectional. The sibling package haze shipped a maintenance release 56 minutes later, marking this as a coordinated sweep across the maintainer's neuroimaging stack.
◆ Prediction
With the four template-by-method combinations closed and the coordinate bug fixed, the next release is more likely to be CRAN-adjacent packaging or documentation than new mapping capability.
Alternatives to lstar and regfusionr
Other Analytics products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either lstar or regfusionr.
piecepackr
A board game graphics package runs one of the most disciplined deprecation cycles in R.
e2tree
The explainable-ensemble-tree package now measures whether its own explanations are faithful.
discretefdr
The discrete-data FDR package is being pared into one piece of a larger multiple-testing suite.
contentanalysis
A scientific-text analysis package moved from counting citations to classifying argument structure.
relialearnr
The teaching arm of an R reliability suite keeps pace with whatever its analysis siblings ship.
See all lstar alternatives → · See all regfusionr alternatives →
Recent activity from lstar and regfusionr
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 18d agoregfusionrVersion 0.3.0 -- vol_to_fsaverage, many convenience functions and fixes ⚡
- 21d agolstarViewer count-basis orientation fixed; existing stores need re-prep
- 26d agolstarWASM viewer crash on resizable heaps fixed
- 1mo agolstarlstar 0.2.0 ⚡
- 1mo agolstarMeasure state inferred from content, not slot name
- 4y agoregfusionrv0.2.0 -- surface to volume data projection
- 4y agoregfusionrv0.1.0: Initial release
Frequently asked questions
What is the difference between lstar and regfusionr?
They serve adjacent needs but don't currently overlap on shipped themes. lstar is currently shipping more aggressively (velocity 5.0 vs 3.8), with 0 editorial sparks in the last 30 days against 1. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is lstar better than regfusionr?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. lstar is currently shipping more aggressively (velocity 5.0 vs 3.8), with 0 editorial sparks in the last 30 days against 1. For your specific use case, the alternatives sections above list other Analytics products to evaluate alongside.
What are the best alternatives to lstar?
Top lstar alternatives in Analytics are ranked by recent ship velocity. Browse the "lstar alternatives" section above for the current picks, or visit /alternatives/lstar for the full list with editorial commentary on each.
What are the best alternatives to regfusionr?
Top regfusionr alternatives in Analytics are ranked by recent ship velocity. Browse the "regfusionr alternatives" section above for the current picks, or visit /alternatives/regfusionr for the full list with editorial commentary on each.