# Accelerator Oscillator

`D07-F03-A14` · Technical Indicators → Momentum · archetype `series-transform` · difficulty 2/5 · verification **verified**

Full page: https://docs.thefintechbuilder.com/technical-indicators/momentum/accelerator-oscillator/
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 { acceleratorOscillator } from "fintech-algorithms/technical-indicators/momentum/accelerator-oscillator";
```

## Signature

```ts
acceleratorOscillator(input)
```

Subtracts a 5-period simple average of the Awesome Oscillator from the oscillator itself, isolating the change in momentum rather than its level.

## Parameters

| Name | Type | Required | Notes |
| --- | --- | --- | --- |
| `input` | `TopicInput` | yes | `bars` is a chronological array of OHLCV rows, each with a non-empty `timestamp` plus finite `open`, `high`, `low`, `close` and `volume`. This topic reads no keys from `parameters`: the underlying 5/34 median-price averages and the 5-period signal are all fixed lengths. The shared momentum preamble still validates `period` (default 14), `fast_period` (default 5) and `slow_period` (default 34) before branching, so a bad value for any of them throws even though this topic reads none of them. |

## Returns

`TopicResult`

`series` and `latest` carry one key, `value`, the Awesome Oscillator minus its own 5-period simple average. Its warm-up is longer than the Awesome Oscillator's because the signal average must itself fill.

## Warm-up

The first `37 bars` positions are `null`. The Awesome Oscillator first resolves at index 33, and its 5-period average needs four more bars, so the first non-null lands at index 37 and `ready_at` is 37 on the canonical fixture.

## Errors

- When `period` is supplied but is not an integer >= 2, even though this topic ignores it — throws Error
- When a bar's `volume` is negative — throws Error

## Complexity

Time `O(n)`, 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
acceleratorOscillator(input)
```

### Returns

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

```json
{
  "topic_id": "D07-F03-A14",
  "title": "Accelerator Oscillator",
  "state": "calculated",
  "ready": true,
  "ready_at": 37,
  "series": {
    "value": [null, null, null, null, null, null]
  },
  "latest": {
    "value": -1.2120760466823697
  },
  "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/technical-indicators/momentum/accelerator-oscillator/
- Implementation source: https://github.com/IslamBaraka90/Fintech-Algorithms-Library/blob/main/src/technical-indicators/momentum/accelerator-oscillator/impl.ts
- Package on npm: https://www.npmjs.com/package/fintech-algorithms
- Domain index for agents: https://docs.thefintechbuilder.com/technical-indicators/llms.txt