# Breakout Strength

`D08-F07-A03` · Geometric Chart Patterns → Market Structure, Breakouts, and Regimes · archetype `record-transform` · difficulty 2/5 · verification **verified**

Full page: https://docs.thefintechbuilder.com/geometric-chart-patterns/market-structure-breakouts-and-regimes/breakout-strength/
Agent skill: `npx skills add IslamBaraka90/Fintech-Algorithms-Library` — https://docs.thefintechbuilder.com/guides/agent-skill/

## Install and import

```bash
npm install fintech-algorithms
```

```ts
import { breakoutStrength } from "fintech-algorithms/geometric-chart-patterns/market-structure-breakouts-and-regimes/breakout-strength";
```

## Signature

```ts
breakoutStrength(input)
```

Expresses how far a close sits beyond its Donchian channel in units of ATR, so a two-tick break in a quiet market and a two-tick break in a violent one do not score the same. Values are negative while price is inside the channel.

## Parameters

| Name | Type | Required | Notes |
| --- | --- | --- | --- |
| `input` | `TopicInput` | yes | `bars` is the required OHLCV history, strictly ordered by `timestamp` and on a single adjustment basis. `parameters.period` (default `20`, integer of at least 2) sets both the channel lookback and the ATR length. |

## Returns

`TopicResult`

`series` and `latest` carry `up_strength` - `(close - upper) / ATR` - and `down_strength` - `(lower - close) / ATR`. The channel levels themselves are not emitted. The warm-up is `period` bars, so with the default `ready_at` is 20; either series is additionally null on any bar where the ATR is zero.

## Warm-up

The first `period bars (20 by default)` positions are `null`. The ATR seed completes at index `period - 1` but the channel needs a full prior window, so the binding constraint is index `period`.

## Errors

- When `period` is supplied as a non-integer or as a value below 2 — throws Error
- When a bar's `high`, `low`, or `close` is not a finite number — throws Error

## Complexity

Time `O(n × period)`, space `O(n)`.

## Worked example

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`:

```json
{
  "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

```ts
breakoutStrength(input)
```

### Returns

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

```json
{
  "topic_id": "D08-F07-A03",
  "title": "Breakout Strength",
  "state": "calculated",
  "ready": true,
  "ready_at": 20,
  "series": {
    "up_strength": [null, null, null, null, null, null],
    "down_strength": [null, null, null, null, null, null]
  },
  "latest": {
    "up_strength": -3.054182842170858,
    "down_strength": -0.09282216777684109
  },
  "parameters": {},
  "diagnostics": {
    "causal": true,
    "input_count": 96
  }
}
```

## Verification and provenance

Tier: **verified** (via E).

The worked example below is the figure published in this algorithm's article, replayed and asserted by the test suite on every build. The arithmetic cannot drift without the build failing.

Both tiers guarantee the signature. Full explanation: https://docs.thefintechbuilder.com/guides/verification/

Generated from the docs.json payload shipped inside fintech-algorithms@0.13.0.
The signature and parameter list are checked against the compiled implementation at build time,
so a description that contradicts the code fails the build rather than reaching this file.

## Links

- Article (how it works, step by step): https://thefintechbuilder.com/geometric-chart-patterns/market-structure-breakouts-and-regimes/breakout-strength/
- Implementation source: https://github.com/IslamBaraka90/Fintech-Algorithms-Library/blob/main/src/geometric-chart-patterns/market-structure-breakouts-and-regimes/breakout-strength/impl.ts
- Package on npm: https://www.npmjs.com/package/fintech-algorithms
- Domain index for agents: https://docs.thefintechbuilder.com/geometric-chart-patterns/llms.txt