kingchenc
6b8c6a0e7f
Adds six **Volatility & Bands** indicators (Part B5 of the expansion roadmap), 423 → 429. | Indicator | Input → Output | Summary | |-----------|----------------|---------| | `EwmaVolatility` | `f64` → `f64` | RiskMetrics exponentially-weighted volatility (λ decay) | | `Garch11` | `f64` → `f64` | GARCH(1,1) conditional volatility with a long-run-variance anchor | | `BipowerVariation` | `f64` → `f64` | jump-robust realized bipower variation (π/2 · Σ\|rₜ\|\|rₜ₋₁\|) | | `VolatilityRatio` | `Candle` → `f64` | Schwager's true range over the EMA of prior true ranges (>2 = wide-ranging day) | | `VolatilityCone` | `Candle` → `VolatilityConeOutput` | current realized volatility within its min/median/max envelope + percentile | | `VolatilityOfVolatility` | `f64` → `f64` | sample stddev of a rolling realized-volatility series | ### Notes - Two B5 roadmap items were dropped as duplicates/by-construction: `RealizedVolatility` already ships (v0.5.4); `Downside Semi-Deviation` is internal to Sortino. `Bipower Variation` confirmed distinct from `JumpIndicator` (a ±1 flag, not a variance measure). - `VolatilityRatio` implements the widely-charted EMA-of-true-range convention (denominator excludes the current bar so the 2.0 threshold means "twice typical"), distinct from the existing pairwise `variance_ratio`. - `Garch11` mean-reverts to `ω/(1−β)` on a flat series (does not decay to 0 like EWMA) — pinned by a dedicated test. ### Coverage / verification - Full core + Python/Node/WASM bindings, fuzz drivers (scalar + candle), registries, CHANGELOG, README + docs counter sync. - 100% unit-test coverage per indicator (every branch). - Green locally: `cargo clippy --workspace --all-targets --all-features -D warnings`, core lib (3479) + doc (387), node (504), python (830). Deep-dive docs for all six are staged for `wickra-docs` and pushed after release (gated).
Fuzzing Wickra
cargo-fuzz harnesses for
the parsing and stateful entry points of Wickra. Fuzzing requires a nightly
Rust toolchain.
Setup
cargo install cargo-fuzz
rustup toolchain install nightly
Targets
| Target | What it exercises |
|---|---|
csv_reader |
CandleReader over arbitrary bytes — headers, cells, BOM, binary noise. |
binance_envelope |
RawWsEnvelope deserialization from arbitrary strings. |
indicator_update |
Every scalar-input indicator (SMA / EMA / WMA / RSI / DEMA / TEMA / HMA / ROC / TRIX / SMMA / TRIMA / ZLEMA / KAMA / T3 / MOM / CMO / TSI / PMO / StochRSI / DPO / PPO / Coppock / StdDev / UlcerIndex / HistoricalVolatility / LinearRegression / LinRegSlope / LinRegAngle / VHF / ZScore / MACD / Bollinger) streamed + batched over arbitrary f64 sequences (NaN, ±inf, jumps). |
indicator_update_candle |
Every candle-input indicator (ATR, NATR, TrueRange, ChaikinVolatility, Keltner, Donchian, PSAR, SuperTrend, ChandelierExit, ChandeKrollStop, ATRTrailingStop, ADX, Aroon, AroonOscillator, Vortex, MassIndex, ChoppinessIndex, CCI, WilliamsR, AwesomeOscillator, AcceleratorOscillator, UltimateOscillator, BalanceOfPower, OBV, MFI, VWAP, RollingVWAP, VWMA, ADL, VPT, CMF, ChaikinOscillator, ForceIndex, EaseOfMovement, TypicalPrice, MedianPrice, WeightedClose, Stochastic) streamed + batched over fuzz-derived OHLCV candles. |
tick_aggregator |
TickAggregator over arbitrary (price, volume, timestamp) triples. |
Run
# From the repository root:
cargo +nightly fuzz run csv_reader
cargo +nightly fuzz run binance_envelope
cargo +nightly fuzz run indicator_update
cargo +nightly fuzz run indicator_update_candle
cargo +nightly fuzz run tick_aggregator
Each run continues until a crash is found or it is interrupted. A short time-boxed smoke run is useful in CI:
cargo +nightly fuzz run csv_reader -- -max_total_time=60
The expectation for every target is that it never panics: malformed or
adversarial input must surface as an Err, never a crash.