mice
mice can finally predict, not just estimate, from multiply imputed data.
A side-by-side editorial comparison of massProps and rollupTree — release velocity, themes, recent moves, and the top alternatives to consider.
A mass-properties rollup spends a year on documentation and follows its sibling's API
massProps computes mass, centre of mass and inertia tensors — and their uncertainties — over tree-structured assemblies, the calculation systems engineers run on a spacecraft or vehicle breakdown. It sits on top of rollupTree, the same author's generic recursive-computation engine, and its most recent release exists only to adopt accessor functions that sibling added two weeks earlier.
The recursive-computation engine under massProps grows the accessors its consumer needed
rollupTree performs recursive computations over tree and DAG structures — the generic engine that its author's massProps package uses to roll mass properties up an assembly breakdown. It is small and moves slowly: five releases in a year, of which two are README and vignette work. The current surface added row-level get and set accessors by key and by id at 0.4.0.
massProps computes mass, centre of mass and inertia tensors — and their uncertainties — over tree-structured assemblies, the calculation systems engineers run on a spacecraft or vehicle breakdown. It sits on top of rollupTree, the same author's generic recursive-computation engine, and its most recent release exists only to adopt accessor functions that sibling added two weeks earlier.
Every release in the window is documentation, benchmarks, or keeping in step with rollupTree. The inertia tensor and radius-of-gyration uncertainty equations have been reformatted and re-explained three separate times, which suggests the hard part of this package is not the computation but making the covariance treatment legible to the engineers meant to trust it. Development effort clearly sits in the engine underneath, not here.
The pattern is unambiguous: rollupTree ships an API change and massProps follows within a fortnight. Whatever the engine does next is what appears here next, and on this evidence it will arrive as a one-line release note.
rollupTree performs recursive computations over tree and DAG structures — the generic engine that its author's massProps package uses to roll mass properties up an assembly breakdown. It is small and moves slowly: five releases in a year, of which two are README and vignette work. The current surface added row-level get and set accessors by key and by id at 0.4.0.
The package develops in response to its one visible consumer. The 0.4.0 accessors appeared in January 2026 and massProps switched to them thirteen days later; 0.4.1 then fixed missing column names in the setters, which is the kind of defect only real use surfaces. Before that, 0.3.0's default_validate_dag() extended validation past strict trees to directed acyclic graphs, widening what structures the engine will accept.
On the established pattern the next release will be whatever massProps needs next, discovered by using it. A DAG validator suggests non-tree structures are in scope, but nothing in these notes says that path is being pushed further.
Other Infra & APIs 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 massProps or rollupTree.
mice can finally predict, not just estimate, from multiply imputed data.
A market-microstructure toolkit that keeps adding estimators as the papers land.
A vowel-analysis package trimming dependencies after an email address got it archived.
The R half of the EMU speech database system, fixing what was quietly broken.
A Bayesian model-averaging package spending its 2.0 on memory, not methods.
tidyplots keeps rebuilding its own foundations rather than layering around them.
See all massProps alternatives → · See all rollupTree alternatives →
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
Both compete on the same themes — systems-engineering — within Infra & APIs. massProps and rollupTree are shipping at a similar cadence (velocity 0.0 vs 0.0, both within Sparkpulse's "active" band). See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. massProps and rollupTree are shipping at a similar cadence (velocity 0.0 vs 0.0, both within Sparkpulse's "active" band). For your specific use case, the alternatives sections above list other Infra & APIs products to evaluate alongside.
Top massProps alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "massProps alternatives" section above for the current picks, or visit /alternatives/massprops for the full list with editorial commentary on each.
Top rollupTree alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "rollupTree alternatives" section above for the current picks, or visit /alternatives/rolluptree for the full list with editorial commentary on each.