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massProps

INFRA · APIS
Velocity0.0

Calculate Mass Properties and Uncertainties of Tree Structures

github.com/jsjuni/massprops ↗

A mass-properties rollup spends a year on documentation and follows its sibling's API

systems-engineeringmass-propertiesuncertainty-propagationdocumentationsibling-package
◆Current state
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.
◆Where it's heading
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.
◆Prediction
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.

◆Recent moves

  1. 6mo ago

    Switched to rollupTree's new row accessors

    A one-line release adopting df_get_by_id() and df_set_by_id() from rollupTree, added there thirteen days earlier. Nothing changes for users; it is the sibling relationship in its clearest form.

    View source ↗
  2. 6mo ago

    Error in the inertia tensor uncertainty documentation

    A documentation correction to the uncertainty equations — the third release in a row to touch how this maths is presented rather than how it is computed.

    View source ↗
  3. 1y ago

    Benchmark results and equation layout cleaned up

    Presentation work on the benchmarks and the inertia tensor equations, with no change to the computation itself.

    View source ↗
  4. 1y ago

    Combine functions given consistent formal parameters

    The one release in the window with a visible API change: the combine functions are made consistent in their formal parameters. The other four items are vignette cleanup and a clearer exposition of the covariance treatment behind radius-of-gyration uncertainty.

    View source ↗
  5. 1y ago

    Examples shrunk to fit CRAN runtime limits

    Example sizes reduced so package checks finish inside CRAN's time budget. Purely mechanical.

    View source ↗