Four-Price Doji

Install and import#

npm install fintech-algorithms

import { fourPriceDoji } from "fintech-algorithms/price-action-and-candlesticks/single-candle-patterns/four-price-doji";

Signature#

fourPriceDoji(input)

Marks each bar whose entire range and whose open-to-close distance both sit within a tick tolerance, the degenerate candle where all four prices are effectively the same.

Parameters#

Returns#

TopicResult

series.label is "neutral" when both high minus low and the absolute open-to-close distance are within tick_tolerance, and "none" otherwise. series.score is tick_tolerance minus the larger of those two distances, so it is at or above zero exactly when the bar matches. latest carries the last value of each. There is no warm-up: unlike its siblings this topic has no positive-span guard, so both series hold a value for every bar and ready_at is 0.

Warm-up#

The first 0 bars positions are null. Purely per-bar arithmetic with no smoothing state and no span guard, so neither label nor score is ever null and ready_at is 0.

Errors#

• When a bar has a non-finite price or volume, a negative volume, a high below its own open/low/close, a low above them, or a timestamp that does not advance — throws Error
• When tick_tolerance is not a finite number or is negative — throws Error
• When input is not an object, input.parameters is not an object, or bars is not an array holding at least one bar — throws Error

Complexity: time O(n), space O(n).

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#

{
  "bars": [
    {
      "timestamp": "2024-01-02",
      "basis": "synthetic-unadjusted",
      "open": 100,
      "high": 101.45,
      "low": 98.695,
      "close": 100,
      "volume": 750000,
      "benchmark": 200
    },
    {
      "timestamp": "2024-01-03",
      "basis": "synthetic-unadjusted",
      "open": 101.49111452,
      "high": 103.38381693,
      "low": 100.05480022,
      "close": 101.78791214,
      "volume": 795117,
      "benchmark": 200.56326135
    },
    {
      "timestamp": "2024-01-04",
      "basis": "synthetic-unadjusted",
      "open": 102.45519048,
      "high": 104.6701838,
      "low": 100.91147007,
      "close": 102.9549389,
      "volume": 840234,
      "benchmark": 201.11020913
    }
  ],
  "parameters": {}
}

Call#

fourPriceDoji(input)

Returns#

object with 9 fields: topic_id, title, state, ready, ready_at, series, latest, parameters, …

{
  "topic_id": "D06-F02-A11",
  "title": "Four-Price Doji",
  "state": "calculated",
  "ready": true,
  "ready_at": 0,
  "series": {
    "label": ["none", "none", "none", "none", "none", "none"],
    "score": [
      -2.74500000000001,
      -3.3190167099999908,
      -3.748713730000011,
      -3.928635059999996,
      -3.819996080000001,
      -3.4596505999999945
    ]
  },
  "latest": {
    "label": "none",
    "score": -3.1108633100000045
  },
  "parameters": {},
  "diagnostics": {
    "causal": true,
    "input_count": 96
  }
}

Diagrams#

Calculation flow#

flowchart LR
    A["one closed OHLC candle, tick size, prior-only reference sc"] --> B["Validate order, basis, and finite values"]
    B --> C["Apply the selected Four-Price Doji convention"]
    C --> D["Emit value, readiness, and diagnostics"]
    D --> E["Interpret descriptively; test outcomes separately"]
    B -->|invalid or insufficient| X["Withhold output with a reason"]

stateDiagram-v2
    [*] --> Waiting
    Waiting --> Ready: enough valid causal observations
    Waiting --> Rejected: malformed or unsupported input
    Ready --> Calculated: selected formula applied
    Calculated --> Interpreted: diagnostic and limitation retained
    Interpreted --> Ready: next observation arrives
    Rejected --> Waiting: corrected input and deterministic reset

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#

• TA-Lib pattern-recognition catalog — see linked primary or authoritative record
• CME Group candlestick chart lesson — see linked primary or authoritative record
• Japanese Candlestick Charting Techniques — see linked primary or authoritative record
• Evidence decision
• Level 1 evidence map

The rest of the Single-Candle Patterns family#

• DojiEvaluates one candle against the repository's explicit doji geometry and scale convention.
• Dragonfly DojiEvaluates one candle against the repository's explicit dragonfly-doji geometry and scale convention.
• Gravestone DojiEvaluates one candle against the repository's explicit gravestone-doji geometry and scale convention.
• MarubozuEvaluates one candle against the repository's explicit marubozu geometry and scale convention.
• Spinning TopEvaluates one candle against the repository's explicit spinning-top geometry and scale convention.
• HammerEvaluates one candle against explicit hammer geometry, scale, and downtrend context conventions.
• Hanging ManEvaluates one candle against explicit hanging-man geometry, scale, and uptrend context conventions.
• Inverted HammerEvaluates one candle against explicit inverted-hammer geometry, scale, and downtrend context conventions.
• Shooting StarEvaluates one candle against explicit shooting-star geometry, scale, and uptrend context conventions.
• Long-Legged DojiMarks each bar whose body is a small fraction of its high-low span while both shadows are long, and reports how much slack the …
• High-Wave CandleMarks each bar with a small body relative to its high-low span whose two shadows are both a multiple of that body, the long-tai…
• Belt HoldMarks each bar that opens at one extreme of its own range within a tick and closes at least 60 percent of the span away, and re…