datefixR
The messy-date parser rewrote its core in Rust and came out 300x faster.
Comparison · Analytics
epidemics vs fellingdater
A side-by-side editorial comparison of epidemics and fellingdater — release velocity, themes, recent moves, and the top alternatives to consider.
epidemics vs fellingdater: at a glance
What is epidemics?
epidemics swapped its C++ engine for odin — and quietly inverted how contact matrices must be passed.
epidemics ships composable compartmental model structures — default SEIR-V, Vacamole, diphtheria and Ebola — with classes for populations, interventions and vaccination campaigns. After more than two years without a release, 0.5.0 landed in July 2026 carrying both an engine migration and a breaking input-convention change. Maintainership moved to a new lead back in 0.4.0.
What is fellingdater?
Went from estimating felling dates to doing the crossdating that produces them.
fellingdater estimates when a tree was felled from sapwood measurements, the core inference in dendrochronological dating of timber. Version 1.0.0 passed rOpenSci review with that scope, and the 2024 releases were mostly about the accompanying JOSS paper and user-supplied sapwood datasets. Version 1.2.0 changed the package's remit substantially, adding an entire trs_* family for tree-ring series handling: crossdating with multiple statistical measures, the Hollstein and Baillie-Pilcher t-value transformations, parallel variation percentages, synthetic series generation, and dated-series plotting.
epidemics vs fellingdater: editorial side-by-side
epidemics
3.8ANALYTICS
epidemics swapped its C++ engine for odin — and quietly inverted how contact matrices must be passed.
◆ Current state
epidemics ships composable compartmental model structures — default SEIR-V, Vacamole, diphtheria and Ebola — with classes for populations, interventions and vaccination campaigns. After more than two years without a release, 0.5.0 landed in July 2026 carrying both an engine migration and a breaking input-convention change. Maintainership moved to a new lead back in 0.4.0.
◆ Where it's heading
The package's history is a sequence of deliberate breaking releases: 0.2.0 renamed every model function and vectorised the ODE models, 0.3.0 restructured the Ebola model into two levels and made replicates the default, and 0.5.0 rewrites the compiled core. The direction is toward a smaller, more declarative model definition layer with the numerical work delegated to a dedicated tool.
◆ Prediction
With the default, Vacamole and diphtheria systems now declared in odin, the Ebola model is the obvious remaining candidate for the same treatment.
fellingdater
0.0ANALYTICS
Went from estimating felling dates to doing the crossdating that produces them.
◆ Current state
fellingdater estimates when a tree was felled from sapwood measurements, the core inference in dendrochronological dating of timber. Version 1.0.0 passed rOpenSci review with that scope, and the 2024 releases were mostly about the accompanying JOSS paper and user-supplied sapwood datasets. Version 1.2.0 changed the package's remit substantially, adding an entire trs_* family for tree-ring series handling: crossdating with multiple statistical measures, the Hollstein and Baillie-Pilcher t-value transformations, parallel variation percentages, synthetic series generation, and dated-series plotting.
◆ Where it's heading
The package has expanded backwards along the workflow. It began at the last step — given dated series, estimate the felling date — and 1.2.0 added the step before it, establishing those dates by crossdating in the first place. Version 1.2.1 is early polish on that new surface: axis control, non-syntactic column names, encoding safety in read_fh(). The direction is a single package covering the chain from raw ring widths to a felling-date estimate.
◆ Prediction
Expect the trs_* family to keep accumulating polish and additional crossdating statistics, since it is barely a year old and 1.2.1 was already fixing its plotting and top_n behaviour. Whether the two halves of the package get unified into one workflow interface is the open question the entries do not answer.
Alternatives to epidemics and fellingdater
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 epidemics or fellingdater.
maplegend
The legend engine mapsf spun out, now covering legend types the parent map package can draw.
lang
R help pages translated on demand by whichever LLM you point it at.
mapsf
Thematic mapping in base R that finally got a theming system, then spent two years polishing legends.
qualtRics
qualtRics moved its contact functions onto XM Directory days before the old endpoints died.
fabletools
The tidyverts forecasting core rebuilt model combination on full residual covariance.
See all epidemics alternatives → · See all fellingdater alternatives →
Recent activity from epidemics and fellingdater
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 25d agoepidemicsODE models migrate to odin; contact matrices must no longer be transposed ⚡
- 4mo agofellingdaterPolish for the crossdating plots and file reader
- 1y agofellingdaterAdds a full crossdating and tree-ring analysis toolkit ⚡
- 1y agofellingdaterUser-supplied sapwood data works across all functions
- 1y agofellingdaterFixes fd_report() with user-defined sapwood files
- 2y agoepidemicsPeak timing and scenario comparison helpers; negative-susceptible bug fixed
- 2y agofellingdaterJOSS paper accepted; citation updated
- 2y agofellingdaterAdds a workflow vignette ahead of JOSS submission
- 2y agoepidemicsEbola model accepts vector inputs and defaults to 100 replicates
- 2y agoepidemicsODE models vectorised; every model function renamed
- 2y agoepidemicsFirst release: four composable compartmental model structures
Frequently asked questions
What is the difference between epidemics and fellingdater?
They serve adjacent needs but don't currently overlap on shipped themes. epidemics 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 epidemics better than fellingdater?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. epidemics 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 epidemics?
Top epidemics alternatives in Analytics are ranked by recent ship velocity. Browse the "epidemics alternatives" section above for the current picks, or visit /alternatives/epidemics for the full list with editorial commentary on each.
What are the best alternatives to fellingdater?
Top fellingdater alternatives in Analytics are ranked by recent ship velocity. Browse the "fellingdater alternatives" section above for the current picks, or visit /alternatives/fellingdater for the full list with editorial commentary on each.