EveningDojiStar

Three-bar bearish top reversal. A long white bar extends the advance, a doji gaps up above it (the star of indecision), then a black bar gaps back down and closes deep into the first body, confirming the turn.

Quick reference

Field	Value
Family	Candlestick Patterns
Input type	Candle
Output type	f64 — -1.0 bearish, 0.0 otherwise (never +1.0)
Output range	{-1.0, 0.0}
Default parameters	penetration = 0.3 (TA-Lib default); bindings use the default
Warmup period	3 (first two bars always 0.0)
Interpretation	Confirmed bearish top reversal

Formula

long body = |close − open| >= 0.5 · (high − low)
doji      = |close − open| <= 0.1 · (high − low)
bar1 white & long
bar2 doji, body gaps UP above bar1 body      (min(o2,c2) > close1)
bar3 black, body gaps DOWN below the doji     (max(o3,c3) < min(o2,c2))
bar3 closes deep into bar1 body               (close3 < close1 − penetration · body1)

Bearish-only (never +1.0); the bullish mirror is MorningDojiStar. The doji variant of the classic evening star — the indecision candle is specifically a doji. See crates/wickra-core/src/indicators/evening_doji_star.rs.

Parameters

Name	Type	Default	Valid range	Source
penetration	f64	0.3	[0.0, 1.0)	EveningDojiStar::with_penetration (evening_doji_star.rs)

with_penetration outside [0, 1) errors (rejects_invalid_penetration, accepts_valid_penetration). Python/Node construct with the default.

Signed ±1 encoding

Single-direction shape: −1.0 bearish, 0.0 no pattern — one feature-matrix dimension.

Inputs / Outputs

use wickra::{Indicator, EveningDojiStar, Candle};
// EveningDojiStar: Input = Candle, Output = f64
const _: fn(&mut EveningDojiStar, Candle) -> Option<f64> = <EveningDojiStar as Indicator>::update;

• Always emits a value. Never None; warmup and no-match bars return 0.0.
• Node. update(open, high, low, close) → number; batch(open, high, low, close) → Array<number>.
• Python. update(candle) → float; batch(open, high, low, close) → 1-D numpy.ndarray (0.0 on warmup / no-match).

Warmup

warmup_period() == 3. The first two bars return 0.0 (first_two_bars_return_zero, accessors_and_metadata).

Edge cases

• Middle must be a doji. A real-bodied star yields 0.0 (middle_not_doji_yields_zero); for the non-doji star use MorningEveningStar.
• Close must penetrate the first body. A shallow third close yields 0.0 (shallow_close_yields_zero).
• Reset. reset() clears the two-bar cache (reset_clears_state).

Examples

Rust

use wickra::{Candle, EveningDojiStar, Indicator};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut t = EveningDojiStar::new();
    println!("{:?}", t.update(Candle::new(10.0, 15.1, 9.9, 15.0, 1.0, 0)?));  // long white
    println!("{:?}", t.update(Candle::new(17.0, 17.1, 16.9, 17.0, 1.0, 1)?)); // doji, gaps up
    println!("{:?}", t.update(Candle::new(16.0, 16.1, 11.9, 12.0, 1.0, 2)?)); // black, deep close
    Ok(())
}

Output:

Some(0.0)
Some(0.0)
Some(-1.0)

The doji gaps above the white close (15), and the black bar closes at 12.0 — deep into the white body — an evening doji star. This matches evening_doji_star_is_minus_one.

Python

import numpy as np
import wickra as ta

o = np.array([10.0, 17.0, 16.0])
h = np.array([15.1, 17.1, 16.1])
l = np.array([9.9,  16.9, 11.9])
c = np.array([15.0, 17.0, 12.0])

print(ta.EveningDojiStar().batch(o, h, l, c))  # [ 0.  0. -1.]

Node

const ta = require('wickra');
const t = new ta.EveningDojiStar();
t.update(10, 15.1, 9.9, 15);
t.update(17, 17.1, 16.9, 17);
console.log(t.update(16, 16.1, 11.9, 12)); // -1

Streaming

use wickra::{Candle, Indicator, EveningDojiStar};

let mut t = EveningDojiStar::new();
let candle_stream: Vec<wickra::Candle> = Vec::new(); // your live OHLCV candle feed
for bar in candle_stream {
    if t.update(bar) == Some(-1.0) { /* confirmed bearish top */ }
}

Interpretation

1. Confirmed top. Unlike a bare doji star, the deep-closing third bar confirms the reversal — a strong bearish signal at the top of an advance.
2. Penetration depth. A deeper third close (raise penetration) demands a more decisive reversal and filters weaker setups.
3. Best at resistance. Strongest after an extended advance or into resistance.

Common pitfalls

• Shallow third close. A third bar that barely dips into the first body does not qualify at the default 30 % penetration.
• 24/7 markets. The gaps are body gaps (not full gaps), so this fires more readily than AbandonedBaby on gapless feeds.

References

• Steve Nison, Japanese Candlestick Charting Techniques (1991).

See also

• MorningDojiStar — the bullish mirror.
• MorningEveningStar — the non-doji star pair.
• DojiStar — the two-bar precursor.
• Indicators-Overview — the full taxonomy.