SeparatingLines

Two-bar continuation. After a counter-trend candle, the next candle of the opposite colour opens right back at the prior open and runs as an opening marubozu in the trend direction — the trend "separates" from the pullback and resumes.

Quick reference

Field	Value
Family	Candlestick Patterns
Input type	Candle
Output type	f64 — +1.0 bullish, -1.0 bearish, 0.0 otherwise
Output range	{-1.0, 0.0, +1.0}
Default parameters	none — SeparatingLines::new()
Warmup period	2 (first bar always 0.0)
Interpretation	Trend continuation after a one-bar counter-move

Formula

long body = |close − open| >= 0.5 · (high − low)
bar1, bar2 opposite colours
bar2 opens at bar1's open:  |open2 − open1| <= 0.05 · range1
bar2 is a long opening marubozu in its direction:
  white bar2: open2 == low2  (no lower shadow)  -> +1.0
  black bar2: open2 == high2 (no upper shadow)  -> -1.0

The shared open is the "separating line"; the sign follows the second (trend-direction) candle. See crates/wickra-core/src/indicators/separating_lines.rs.

Parameters

None. Constructed with SeparatingLines::new().

Signed ±1 encoding

Emits the uniform candlestick sign convention — +1.0 bullish, −1.0 bearish, 0.0 no pattern — a single feature-matrix dimension.

Inputs / Outputs

use wickra::{Indicator, SeparatingLines, Candle};
// SeparatingLines: Input = Candle, Output = f64
const _: fn(&mut SeparatingLines, Candle) -> Option<f64> = <SeparatingLines 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() == 2. The first bar returns 0.0 (first_bar_returns_zero, accessors_and_metadata).

Edge cases

• Colours must oppose. Same-coloured bars yield 0.0 (same_color_yields_zero).
• Opens must match. A different open yields 0.0 (different_open_yields_zero).
• Opening-side shadow. The second bar must open at its extreme (marubozu open); an opening shadow yields 0.0 (opening_shadow_yields_zero).
• Reset. reset() clears the one-bar cache (reset_clears_state).

Examples

Rust

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

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut t = SeparatingLines::new();
    println!("{:?}", t.update(Candle::new(12.0, 12.1, 9.9, 10.0, 1.0, 0)?)); // black pullback
    println!("{:?}", t.update(Candle::new(12.0, 14.1, 12.0, 14.0, 1.0, 1)?)); // white, opens at 12, runs up
    Ok(())
}

Output:

Some(0.0)
Some(1.0)

The white bar opens at 12.0 (same as bar1's open) with no lower shadow and runs up — a bullish separating line. This matches bullish_separating_lines_is_plus_one.

Python

import numpy as np
import wickra as ta

o = np.array([12.0, 12.0])
h = np.array([12.1, 14.1])
l = np.array([9.9,  12.0])
c = np.array([10.0, 14.0])

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

Node

const ta = require('wickra');
const t = new ta.SeparatingLines();
t.update(12, 12.1, 9.9, 10);
console.log(t.update(12, 14.1, 12, 14)); // 1

Streaming

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

let mut t = SeparatingLines::new();
let candle_stream: Vec<wickra::Candle> = Vec::new(); // your live OHLCV candle feed
for bar in candle_stream {
    match t.update(bar) {
        Some(1.0)  => { /* uptrend resumes after a one-bar dip */ }
        Some(-1.0) => { /* downtrend resumes after a one-bar pop */ }
        _ => {}
    }
}

Interpretation

1. Pullback rejected at the open. Re-opening at the prior open and running the trend way shows the counter-move was a one-bar blip — continuation.
2. Marubozu strength. The trend-direction candle opening at its extreme (no opening shadow) is what gives the signal its conviction.
3. Confirm with the trend. Continuation pattern; use within a trend.

Common pitfalls

• Loose open match. The two opens must be essentially equal (within 5 % of range), not just close.
• Opening shadow. A trend candle with an opening shadow is not a separating line.

References

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

See also

• OpeningMarubozu — the marubozu the second bar forms.
• GapSideBySideWhite — gap-based continuation.
• Indicators-Overview — the full taxonomy.