AAA exponential smoothing (Hyndman et al. 2008, ETS(A,A,A)) over an evenly
spaced timeline: documented seasonality, data completion and aggregation
arguments, calendar-month date timelines, autocorrelation seasonality
detection, state-space prediction intervals, statistic types 1-8.
Smoothing parameters minimise the in-sample SSE (grid + clamped
Nelder-Mead). XLSX export treats the family's range arguments as
array-taking (no spurious dynamic-array metadata), FORECAST/FORECAST.LINEAR
included.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Preserve array evaluation for non-spilling XLSX formulas
Rebased onto main with a maintainer fix-up (LET bindings via split_last/as_chunks for clippy, no slice indexing); the contributor's branch does not allow maintainer edits.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
