fintech-algorithms
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Fractal Chaos Bands

Install and import#

bash
npm install fintech-algorithms
ts
import { fractalChaosBands } from "fintech-algorithms/technical-indicators/bands-envelopes-and-squeezes/fractal-chaos-bands";

Signature#

fractalChaosBands(input)

Fractal Chaos Bands: carries forward the most recent confirmed five-bar fractal high and fractal low, each held flat until a new fractal of that side confirms.

Parameters#

NameTypeNotes
inputTopicInputbars is the required OHLCV array -- each bar carries timestamp, open, high, low, close, volume and an optional basis, strictly ordered by timestamp. This topic reads no keys of its own from parameters; the five-bar fractal window is fixed in code. period (default 20, integer >= 2) and multiplier (default 2, a finite number >= 0) are read and validated by the band family for every topic in it. Neither is used by this branch, but an invalid value is still rejected.

Returns#

TopicResult

series holds only upper and lower -- there is no center for this topic -- and latest carries the last of each. The warm-up is data dependent: a fractal is confirmed two bars after its pivot, so nothing can appear before index 4, and each side stays null until its first fractal confirms. In the canonical fixture upper first appears at index 5 and lower at index 8, making ready_at 5.

Warm-up#

The first at least 4 bars, then data dependent per side positions are null. Confirmation needs two bars either side of the pivot, so index 4 is the earliest possible reading, and the actual first index depends on when a qualifying high or low occurs. upper and lower can therefore become available on different bars.

Errors#

  • When parameters.period is not an integer >= 2 — throws Error
  • When a bar is missing open, high, low, close, or volume, or one of them is not a finite number — throws Error
  • When bars are not strictly ordered by timestamp, or a bar's high is below its open, low, or close — 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#

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#

fractalChaosBands(input)

Returns#

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

{
  "topic_id": "D07-F07-A08",
  "title": "Fractal Chaos Bands",
  "state": "calculated",
  "ready": true,
  "ready_at": 5,
  "series": {
    "upper": [null, null, null, null, null, 105.01857496],
    "lower": [null, null, null, null, null, null]
  },
  "latest": {
    "upper": 109.83623682,
    "lower": 101.07584902
  },
  "parameters": {},
  "diagnostics": {
    "causal": true,
    "input_count": 96
  }
}

Diagrams#

Fractal Chaos Bands — article hero
Fractal Chaos Bands — concept map
Fractal Chaos Bands — decision comparison
Fractal Chaos Bands — worked example

Calculation flow#

Fractal Chaos Bands calculation flow
flowchart LR
    A["ordered OHLC or close observations, a declared centerline,"] --> B["Validate order, basis, and finite values"]
    B --> C["Apply the selected Fractal Chaos Bands 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"]
Fractal Chaos Bands readiness and evidence states
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 function groups — see linked primary or authoritative record
  • TA-Lib C/C++ API — see linked primary or authoritative record
  • TA-Lib maintained source — see linked primary or authoritative record
  • Evidence decision
  • Level 1 evidence map

The rest of the Bands, Envelopes, and Squeezes family#