InNeck

Two-bar bearish continuation, slightly stronger than On-Neck. A long black candle in a decline is followed by a white candle that opens below the black bar's low and closes just barely into the black body, around its close level. The shallow recovery still favours the sellers.

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	none — InNeck::new()
Warmup period	2 (first bar always 0.0)
Interpretation	Bearish continuation; bounce just into the body

Formula

long body = |close − open| >= 0.5 · (high − low)
bar1 black & long
bar2 white, opens below bar1's low:        open2 < low1
bar2 closes just into bar1's body:          close1 <= close2 <= close1 + 0.1 · body1

Bearish-only (never +1.0). The bounce recovers marginally above the prior close — deeper than OnNeck (to the low) but far short of a reversal. See crates/wickra-core/src/indicators/in_neck.rs.

Parameters

None. Constructed with InNeck::new().

Signed ±1 encoding

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

Inputs / Outputs

use wickra::{Indicator, InNeck, Candle};
// InNeck: Input = Candle, Output = f64
const _: fn(&mut InNeck, Candle) -> Option<f64> = <InNeck 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 array.array('d') (0.0 on warmup / no-match).

Warmup

warmup_period() == 2. The first bar returns 0.0 (first_bar_returns_zero, accessors_and_metadata).

Edge cases

• Close at the low. A close right at the prior low is On-Neck, not In-Neck (close_at_low_yields_zero).
• Close past the neck zone. A deeper close is Thrusting/piercing (close_past_neck_yields_zero).
• Second bar must be white. Otherwise 0.0 (second_bar_black_yields_zero).
• Reset. reset() clears the one-bar cache (reset_clears_state).

Examples

Rust

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

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut t = InNeck::new();
    println!("{:?}", t.update(Candle::new(15.0, 15.1, 9.0, 10.0, 1.0, 0)?)); // long black, close 10
    println!("{:?}", t.update(Candle::new(7.0, 10.3, 6.9, 10.2, 1.0, 1)?));  // white, closes just into body
    Ok(())
}

Output:

Some(0.0)
Some(-1.0)

The white bar closes at 10.2, just above the black close 10.0 (within 0.1·body) — an in-neck. This matches in_neck_is_minus_one.

Python

import numpy as np
import wickra as ta

o = np.array([15.0, 7.0])
h = np.array([15.1, 10.3])
l = np.array([9.0,  6.9])
c = np.array([10.0, 10.2])

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

Node

const ta = require('wickra');
const t = new ta.InNeck();
t.update(15, 15.1, 9, 10);
console.log(t.update(7, 10.3, 6.9, 10.2)); // -1

Streaming

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

let mut t = InNeck::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) { /* shallow bounce — downtrend continuation */ }
}

Interpretation

1. Still a failed bounce. Recovering only just into the body keeps the bears in charge — bearish continuation.
2. Mid of the neck family. Slightly less bearish than OnNeck, more bearish than Thrusting.
3. Confirm with the trend. Continuation pattern; needs a decline.

Common pitfalls

• Boundary confusion. The close band (just above the prior close) separates In-Neck from On-Neck and Thrusting; small differences change the label.
• No downtrend context. Only meaningful inside a decline.

References

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

See also

• OnNeck — bounce to the low.
• Thrusting — bounce toward mid-body.
• PiercingDarkCloud — the reversal past mid-body.
• Indicators-Overview — the full taxonomy.