# Median Price Transform

`D07-F08-A02` · Technical Indicators → Price Transforms · archetype `series-transform` · difficulty 2/5 · verification **verified**

Full page: https://docs.thefintechbuilder.com/technical-indicators/price-transforms/median-price-transform/
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 { medianPriceTransform } from "fintech-algorithms/technical-indicators/price-transforms/median-price-transform";
```

## Signature

```ts
medianPriceTransform(input)
```

Takes the midpoint of each bar's high and low.

## Parameters

| Name | Type | Required | Notes |
| --- | --- | --- | --- |
| `input` | `TopicInput` | yes | `bars` needs `timestamp`, `high` and `low`. This topic reads no keys from `parameters`, though `parameters` must still be an object when supplied. |

## Returns

`TopicResult`

`series` holds a single `value`, `(high + low) / 2` for every bar, and `latest` its last element. Every bar produces a value, so there is no warm-up.

## Warm-up

The first `none` positions are `not applicable`. `ready_at` is 0. The close is deliberately not part of this midpoint.

## Errors

- When a bar's `high` or `low` is not a finite number — throws Error
- When a `low` is above the bar's `open`, `high` or `close` — throws Error
- When a `timestamp` is missing or not text — 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
medianPriceTransform(input)
```

### Returns

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

```json
{
  "topic_id": "D07-F08-A02",
  "title": "Median Price Transform",
  "state": "calculated",
  "ready": true,
  "ready_at": 0,
  "series": {
    "value": [
      100.07249999999999,
      101.719308575,
      102.790826935,
      103.04925743,
      102.71241351,
      102.27681525
    ]
  },
  "latest": {
    "value": 100.249174165
  },
  "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/price-transforms/median-price-transform/
- Implementation source: https://github.com/IslamBaraka90/Fintech-Algorithms-Library/blob/main/src/technical-indicators/price-transforms/median-price-transform/impl.ts
- Package on npm: https://www.npmjs.com/package/fintech-algorithms
- Domain index for agents: https://docs.thefintechbuilder.com/technical-indicators/llms.txt