Struct BomarBands 

pub struct BomarBands { /* private fields */ }

Bomar Bands: percentage bands whose width adapts so that a fixed coverage fraction of recent closes falls inside them.

The Bomar Bands predate Bollinger Bands; John Bollinger cites them as an inspiration — percentage bands around a moving average, with the percentage tuned so a fixed share (classically ~85%) of price stayed within. Wickra realises that idea deterministically: the half-width is the coverage quantile of the relative deviations from the midline, so by construction coverage of the window’s closes lie inside the bands.

middle = SMA(close, period)
dev_i  = | close_i / middle − 1 |          // relative distance from midline
p      = coverage-quantile of { dev_i }     // type-7 interpolation
upper  = middle + |middle| · p
lower  = middle − |middle| · p

Unlike the fixed-percentage MaEnvelope, the offset here is data-driven: the bands widen in turbulent regimes and tighten in quiet ones without a volatility input. Unlike Bollinger Bands, the width is an order statistic of the actual deviations rather than a multiple of the standard deviation, so it is unaffected by the shape of the tails beyond the coverage rank. When the midline is zero the relative deviation is undefined and the bands collapse onto the midline.

Example

use wickra_core::{BomarBands, Indicator};

let mut indicator = BomarBands::new(20, 0.85).unwrap();
let mut last = None;
for i in 0..40 {
    last = indicator.update(100.0 + f64::from(i % 7));
}
assert!(last.is_some());

Implementations

impl BomarBands

pub fn new(period: usize, coverage: f64) -> Result<Self>

Construct new Bomar Bands.

coverage is the target fraction of closes to contain, in (0.0, 1.0].

Errors

Returns Error::PeriodZero if period == 0, or Error::InvalidParameter if coverage is not a finite value in (0.0, 1.0].

pub const fn period(&self) -> usize

Configured period.

pub const fn coverage(&self) -> f64

Configured coverage fraction.

Trait Implementations

impl Clone for BomarBands

fn clone(&self) -> BomarBands

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BomarBands

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Indicator for BomarBands

type Input = f64

Type of one input data point (typically f64 for a price, or Candle / Tick).

type Output = BomarBandsOutput

Type of one output value.

fn update(&mut self, value: f64) -> Option<BomarBandsOutput>

Feed one new data point into the indicator and return the freshly computed output, or None if the indicator is still warming up.

fn reset(&mut self)

Reset all internal state, leaving the indicator equivalent to a freshly constructed instance with the same parameters.

fn warmup_period(&self) -> usize

Number of inputs required before the first non-None output can be produced.

fn is_ready(&self) -> bool

Whether the indicator has emitted at least one value since the last reset.

fn name(&self) -> &'static str

Stable, human-readable indicator name. Used by chaining and diagnostics.