Struct ElderRay 

pub struct ElderRay { /* private fields */ }

Elder Ray — Alexander Elder’s Bull Power / Bear Power oscillator.

An EMA of the close marks the market’s consensus of value; the bar’s high and low relative to it measure how far the bulls and bears could push price away from that consensus:

ema       = EMA(close, period)
BullPower = high - ema
BearPower = low  - ema

Bull Power is normally positive (the high prints above the mean) and Bear Power normally negative (the low prints below it). Their behaviour relative to zero and to the EMA’s slope drives Elder’s signals: e.g. in an uptrend (rising EMA), a bounce in a negative-but-rising Bear Power is a buy setup.

The first reading lands once the inner EMA is seeded, at bar period.

Example

use wickra_core::{Candle, ElderRay, Indicator};

let mut er = ElderRay::new(13).unwrap();
let mut last = None;
for i in 0..40 {
    let base = 100.0 + f64::from(i);
    let c = Candle::new(base, base + 2.0, base - 2.0, base + 0.5, 1.0, i64::from(i)).unwrap();
    last = er.update(c);
}
assert!(last.is_some());

Implementations

impl ElderRay

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

Construct an Elder Ray with the given EMA period.

Errors

Returns crate::Error::PeriodZero if period == 0.

pub const fn period(&self) -> usize

Configured period.

Trait Implementations

impl Clone for ElderRay

fn clone(&self) -> ElderRay

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ElderRay

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

Formats the value using the given formatter.

impl Indicator for ElderRay

type Input = Candle

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

type Output = ElderRayOutput

Type of one output value.

fn update(&mut self, candle: Candle) -> Option<ElderRayOutput>

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.