First step of the indicator-family expansion (see the F section of
todo-detailed.md). Family F1 — Simple & Weighted MAs — gains two
members alongside the existing Sma/Ema/Wma:
- Smma — Wilder's smoothed moving average (RMA): SMA-seeded, then the
(prev*(n-1)+x)/n recurrence. The average underlying RSI and ATR.
- Trima — triangular moving average: two stacked SMAs (n1/n2 split by
parity) that triangular-weight the window. Genuine stacking — the
outer SMA consumes the inner SMA's output.
Both implement the full Indicator trait with reference-value, warmup,
reset, batch==streaming and non-finite-input tests, a runnable doctest,
and are re-exported from the crate root. 208 core tests + 30 doctests
pass; clippy and fmt clean.