ATR Support and Resistance

Install and import#

npm install fintech-algorithms

import { atrSupportAndResistance } from "fintech-algorithms/geometric-chart-patterns/pivots-and-levels/atr-support-and-resistance";

Signature#

atrSupportAndResistance(input)

Places support and resistance a volatility-scaled distance either side of a simple moving average of close: center ± multiplier × ATR(period), where the ATR is Wilder-smoothed true range.

Parameters#

Returns#

TopicResult

series and latest carry center, support and resistance. The warm-up is period - 1 bars, because the moving average and the ATR seed both complete at index period - 1, so with the default ready_at is 19.

Warm-up#

The first period - 1 bars (19 by default) positions are null. The simple moving average and the Wilder ATR seed both need period observations, and true range is defined from index 0, so all three series turn non-null together at index period - 1.

Errors#

• When multiplier is supplied as a negative number or is not finite — throws Error
• When period is supplied as a non-integer or as a value below 2 — throws Error

Complexity: time O(n × period), 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#

atrSupportAndResistance(input)

Returns#

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

{
  "topic_id": "D08-F01-A12",
  "title": "ATR Support and Resistance",
  "state": "calculated",
  "ready": true,
  "ready_at": 19,
  "series": {
    "center": [null, null, null, null, null, null],
    "support": [null, null, null, null, null, null],
    "resistance": [null, null, null, null, null, null]
  },
  "latest": {
    "center": 104.20055051999998,
    "support": 97.75337766966595,
    "resistance": 110.647723370334
  },
  "parameters": {},
  "diagnostics": {
    "causal": true,
    "input_count": 96
  }
}

Diagrams#

Calculation flow#

flowchart LR
    A["closed OHLC bars or causally confirmed pivots with session"] --> B["Validate order, basis, and finite values"]
    B --> C["Apply the selected ATR Support and Resistance 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#

• CFA Institute technical-analysis overview — see linked primary or authoritative record
• TA-Lib maintained source — see linked primary or authoritative record
• Long-Term Storage Capacity of Reservoirs — see linked primary or authoritative record
• Evidence decision
• Level 1 evidence map

The rest of the Pivots and Levels family#

• Causal Pivot DetectionFinds swing highs and lows using only bars that had already arrived.
• ZigZag SegmentationSegments a series into alternating swings that exceed a percentage threshold.
• Support/Resistance ClusteringGroups nearby pivots into levels.
• Robust Trendline FittingFits a trendline through pivots in log space with outlier resistance.
• Classic and Floor-Trader Pivot PointsProjects the classic floor-trader pivot and two resistance/support pairs for each bar from the previous bar's high, low, and cl…
• Fibonacci Pivot PointsTakes the same (H + L + C) / 3 pivot as the classic variant but places the bands at Fibonacci fractions of the previous bar's…
• Camarilla Pivot PointsAnchors its bands on the previous bar's close rather than on the pivot: r1/s1 sit at close ± 1.1 × range / 12 and r2/`s…
• Woodie Pivot PointsWeights the current bar's open into the pivot, (H_prev + L_prev + 2 × open) / 4, then derives r1/s1 by reflecting that pi…
• DeMark Pivot PointsChooses one of three formulas for the intermediate X depending on whether the previous bar closed below, above, or level with…
• Rolling Support and ResistanceReports, for each bar, the lowest low and highest high of the period bars that came strictly before it.
• Fractal Support and ResistanceHolds the most recent confirmed five-bar fractal high and low forward as resistance and support.
• Pivot Range WidthMeasures the central pivot range rather than its bands: bottom is the previous bar's midpoint (H + L) / 2, top is that mi…