Bearish Engulfing

Install and import#

npm install fintech-algorithms

import { bearishEngulfing } from "fintech-algorithms/price-action-and-candlesticks/two-candle-patterns/bearish-engulfing";

Signature#

bearishEngulfing(inputs)

Evaluates two candles against explicit bearish-engulfing geometry, scale, and uptrend context conventions.

Parameters#

Returns#

{ topic_id, pattern, matched, state, direction, trend_context, required_context, body, upper_shadow, lower_shadow, range, body_scale, range_scale, history_count, geometry_score, checks, failed_checks, first_direction, second_direction, first_body, second_body, first_body_low?, first_body_high?, second_body_low?, second_body_high?, first_high?, second_high?, first_low?, second_low?, midpoint?, price_tolerance }

One pattern record with causal geometry diagnostics. state is warmup, wrong-context, matched, or not-matched; detailed price fields are absent during warmup.

Warm-up#

The first 5 prior observations positions are state: warmup. The detector returns one readiness record before five prior body/range observations are available; it does not emit a positional null prefix.

Errors#

• When candle, history, context, tick-size, or tolerance input violates the data contract — throws

Complexity: time , space .

Worked example#

executed Captured by running this function on the input its own test provides. Real output of real code — but not asserted against a published figure.

Input#

{
  "first": {
    "open": 102,
    "high": 105.5,
    "low": 101.5,
    "close": 105
  },
  "second": {
    "open": 105.5,
    "high": 106,
    "low": 101,
    "close": 101.5
  },
  "prior_bodies": [2, 2.2, 1.8, 2.1, 1.9, 2],
  "prior_ranges": [5, 5, 5, 5, 5, 5],
  "trend_context": "uptrend",
  "tick_size": 0.1,
  "price_tolerance_ticks": 2
}

Call#

bearishEngulfing(inputs)

Returns#

object with 31 fields: topic_id, pattern, matched, state, direction, trend_context, required_context, body, …

{
  "topic_id": "D06-F03-A02",
  "pattern": "Bearish Engulfing",
  "matched": true,
  "state": "matched",
  "direction": "bearish",
  "trend_context": "uptrend",
  "required_context": "uptrend",
  "body": 4,
  "upper_shadow": 0.5,
  "lower_shadow": 0.5,
  "range": 5,
  "body_scale": 2,
  "range_scale": 5,
  "history_count": 10
}

Showing 14 of 31 fields.

Other exports#

This module also exports calculate, shadowToBodyRatio, gapClassification, trendContextFilter, doji, dragonflyDoji, gravestoneDoji, marubozu, spinningTop, hammer, hangingMan, invertedHammer, shootingStar, bullishEngulfing, bullishHarami, bearishHarami, piercingLine, darkCloudCover, tweezerTop, tweezerBottom. Every module additionally exports run as an alias of its primary function, and a meta object carrying its catalog id, domain, family, shape and article URL.

Diagrams#

How it works#

This page states the contract — how to call it correctly. The article explains the concept: why it works, and where it breaks.

Read the article →

References#

• Japanese Candlestick Charting Techniques, Second Edition — Steve Nison
• Technical Insights — Candles in Market Context — CMT Association
• Candlestick Settings — TA-Lib project
• Bearish Engulfing recognizer — TA-Lib project
• Evidence boundary

The rest of the Two-Candle Patterns family#

• Bullish EngulfingEvaluates two candles against explicit bullish-engulfing geometry, scale, and downtrend context conventions.
• Bullish HaramiEvaluates two candles against explicit bullish-harami containment, scale, and downtrend context conventions.
• Bearish HaramiEvaluates two candles against explicit bearish-harami containment, scale, and uptrend context conventions.
• Piercing LineEvaluates two candles against explicit piercing-line gap, midpoint, scale, and downtrend conventions.
• Dark Cloud CoverEvaluates two candles against explicit dark-cloud gap, midpoint, scale, and uptrend conventions.
• Tweezer TopEvaluates two candles against explicit tweezer-top tolerance, rejection, scale, and uptrend conventions.
• Tweezer BottomEvaluates two candles against explicit tweezer-bottom tolerance, rejection, scale, and downtrend conventions.