FallingThreeMethods

Five-bar bearish continuation. A long black candle is followed by three small white bars that drift up with their bodies inside its range (a brief rest), then a second long black candle opens below the last rest bar's close and closes below the first, resuming the decline (Nison; TA-Lib CDLRISEFALL3METHODS).

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 — FallingThreeMethods::new()
Warmup period	5 (first four bars return None)
Interpretation	Bearish continuation after an in-range rest

Formula

long body  = |close − open| >= 0.5 · (high − low)
small body = |close − open| <= 0.5 · body1
bar1 black & long
bar2, bar3, bar4 small white bodies, each real body overlapping bar1's
                 high/low range: min(open, close) < high1 and max(open, close) > low1,
                 with rising closes (close3 > close2, close4 > close3)
bar5 black & long, opening below bar4's close (open5 < close4)
                 and closing below bar1's close (close5 < close1)

Body thresholds follow the geometric house style rather than TA-Lib's rolling averages, and no trend filter is applied. Bearish-only (never +1.0); the bullish mirror is RisingThreeMethods. Only the real body of each rest bar is tested, as in TA-Lib: a shadow may poke above bar1's high or below bar1's low as long as part of the body lies within bar1's high-low range. Earlier releases required the whole bar, shadows included, to stay inside. See crates/wickra-core/src/indicators/falling_three_methods.rs.

TA-Lib parity. On the TA-Lib reference pattern series the −1 signals match the bearish (−100) signals of CDLRISEFALL3METHODS exactly. TA-Lib sizes long and short bodies against rolling averages of the previous bars ("candle settings"); Wickra sizes them against the pattern's own bars.

Parameters

None. Constructed with FallingThreeMethods::new().

Signed ±1 encoding

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

Inputs / Outputs

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

• Warmup is None. The first four bars return None; from bar 5 on every bar returns -1.0 or 0.0 (no match).
• Node. update(open, high, low, close) → number | null; batch(open, high, low, close) → Array<number> (NaN on warmup).
• Python. update(candle) → float | None; batch(open, high, low, close) → 1-D array.array('d') (NaN on warmup, 0.0 on no-match).

Warmup

warmup_period() == 5. The first four bars return None while the five-bar window fills (first_four_bars_return_zero, accessors_and_metadata).

Edge cases

• Middle bodies must overlap bar1's range. A resting bar whose whole body sits above bar1's high or below bar1's low yields 0.0 (middle_bar_breaks_range_yields_zero, middle_body_fully_outside_range_yields_zero); touching the boundary exactly counts as outside. A shadow that pokes out while the body overlaps still qualifies (middle_shadow_outside_range_but_body_overlapping_fires).
• Fifth bar must make a new low. A fifth close that does not clear bar1's close downward yields 0.0 (bar5_not_new_low_yields_zero).
• First bar must be a long black body. A flat first bar (zero range) or a wide-range bar with a tiny body yields 0.0 (zero_range_first_bar_yields_zero, short_first_body_yields_zero).
• Rest bars must be small, white and rising. A middle bar that is black, has a body larger than half of bar1's, or closes at or below the previous rest bar's close yields 0.0.
• Fifth bar must open below bar4's close and be a long black body (body5 >= 0.5 · range5); otherwise 0.0.
• Reset. reset() clears the four-bar cache (reset_clears_state).

Examples

Rust

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

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut t = FallingThreeMethods::new();
    println!("{:?}", t.update(Candle::new(15.0, 15.1, 9.9, 10.0, 1.0, 0)?));  // long black
    println!("{:?}", t.update(Candle::new(11.0, 12.1, 10.9, 12.0, 1.0, 1)?)); // small white, in range
    println!("{:?}", t.update(Candle::new(11.5, 12.6, 11.4, 12.5, 1.0, 2)?)); // small white, higher close
    println!("{:?}", t.update(Candle::new(12.0, 13.1, 11.9, 13.0, 1.0, 3)?)); // small white, higher close
    println!("{:?}", t.update(Candle::new(12.5, 12.6, 8.9, 9.0, 1.0, 4)?));   // long black, opens < 13.0, new low
    Ok(())
}

Output:

None
None
None
None
Some(-1.0)

Three small white bars (bodies 1.0 ≤ 0.5 · 5.0) rest with their bodies inside the first black candle's range with rising closes, then bar 5 — a long black body opening at 12.5, below bar4's close 13.0 — closes at 9.0 below bar1's close 10.0 — falling three methods. This matches falling_three_methods_is_minus_one.

Python

import numpy as np
import wickra as ta

o = np.array([15.0, 11.0, 11.5, 12.0, 12.5])
h = np.array([15.1, 12.1, 12.6, 13.1, 12.6])
l = np.array([9.9,  10.9, 11.4, 11.9, 8.9])
c = np.array([10.0, 12.0, 12.5, 13.0, 9.0])

print(ta.FallingThreeMethods().batch(o, h, l, c))  # array('d', [nan, nan, nan, nan, -1.0])

Node

const ta = require('wickra');
const t = new ta.FallingThreeMethods();
t.update(15, 15.1, 9.9, 10);
t.update(11, 12.1, 10.9, 12);
t.update(11.5, 12.6, 11.4, 12.5);
t.update(12, 13.1, 11.9, 13);
console.log(t.update(12.5, 12.6, 8.9, 9)); // -1

Streaming

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

let mut t = FallingThreeMethods::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) { /* downtrend resumes after an in-range rest */ }
}

Interpretation

1. Healthy pause in a decline. Three small white bars holding inside a strong black candle's range, then a breakdown, is a textbook bearish continuation.
2. Stay short. Read it as a chance to remain with the downtrend rather than to call a bottom.
3. Confirm with the trend. Continuation pattern; use within a downtrend.

Common pitfalls

• Resting body escapes the range. A middle bar whose body lies entirely beyond bar1's high or low disqualifies the setup; a shadow alone poking out does not.
• No breakdown. The fifth candle must close below bar1's close.
• Wrong-coloured or flat rest. The resting bars must be white with each close higher than the last; a black or sideways rest bar disqualifies the setup.
• Weak fifth bar. Bar 5 must open below bar4's close and be a long black body, not just any down bar.

References

• Steve Nison, Japanese Candlestick Charting Techniques (1991).
• TA-Lib CDLRISEFALL3METHODS — reference implementation of the shape rules.

See also

• RisingThreeMethods — the bullish mirror.
• DownsideGapThreeMethods — gap-based bearish continuation.
• Indicators-Overview — the full taxonomy.