qtl2fst
The out-of-memory backend for R/qtl2, feature-complete since 2020 and now purely on upkeep
Comparison · Analytics
PurpleAir vs regfusionr
A side-by-side editorial comparison of PurpleAir and regfusionr — release velocity, themes, recent moves, and the top alternatives to consider.
Shared themes:r-package
PurpleAir vs regfusionr: at a glance
What is PurpleAir?
The R client for PurpleAir sensors keeps finding its time-averaging was wrong.
PurpleAir is a small R client for the PurpleAir air quality sensor API, covering sensor queries, historical readings, and — more recently — finding a sensor on the local network by IP address and id. Authentication has been simplified to an environment variable only, with the redundant key argument removed. The package is maintained reactively, and most of what ships is correctness work on the queries it already makes.
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.
PurpleAir vs regfusionr: editorial side-by-side
PurpleAir
0.0ANALYTICS
The R client for PurpleAir sensors keeps finding its time-averaging was wrong.
◆ Current state
PurpleAir is a small R client for the PurpleAir air quality sensor API, covering sensor queries, historical readings, and — more recently — finding a sensor on the local network by IP address and id. Authentication has been simplified to an environment variable only, with the redundant key argument removed. The package is maintained reactively, and most of what ships is correctness work on the queries it already makes.
◆ Where it's heading
The recurring theme is time aggregation. Weekly, monthly and yearly average intervals were wrong and fixed in one release; the weekly average was wrong again and fixed in the next. For an air quality package that is not incidental — averaging window is what turns a stream of sensor readings into an exposure estimate, and downstream analyses inherit the error silently. The other thread is failing earlier and more clearly: explicit errors for spatial inputs the sensor query does not accept, better index parsing so malformed requests never reach the API, and handling for history calls that return nothing. Local sensor discovery is the one genuine capability addition, opening a path that does not depend on the cloud API at all.
◆ Prediction
On this record, further aggregation and input-validation fixes are the likeliest next releases; whether local network access grows past discovery into full local data retrieval is not something the entries indicate.
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 PurpleAir 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 PurpleAir or regfusionr.
mmconvert
A single-purpose mouse map interpolator that solved its problem in 2023 and has coasted since
qtl2convert
A conversion utility in pure maintenance mode, tracking R-devel breakage release by release
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.
See all PurpleAir alternatives → · See all regfusionr alternatives →
Recent activity from PurpleAir 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 ⚡
- 3mo agoPurpleAirWeekly averages fixed again; API key argument dropped
- 10mo agoPurpleAirLocal sensor discovery, and averaging intervals corrected
- 1y agoPurpleAirBounding box sensor queries fixed
- 4y agoregfusionrv0.2.0 -- surface to volume data projection
- 4y agoregfusionrv0.1.0: Initial release
Frequently asked questions
What is the difference between PurpleAir and regfusionr?
Both compete on the same themes — r-package — within Analytics. regfusionr is currently shipping more aggressively (velocity 3.8 vs 0.0), with 1 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is PurpleAir better than regfusionr?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. regfusionr is currently shipping more aggressively (velocity 3.8 vs 0.0), with 1 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Analytics products to evaluate alongside.
What are the best alternatives to PurpleAir?
Top PurpleAir alternatives in Analytics are ranked by recent ship velocity. Browse the "PurpleAir alternatives" section above for the current picks, or visit /alternatives/purpleair 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.