# confusion-matrix

**Repository Path**: mirrors_mljs/confusion-matrix

## Basic Information

- **Project Name**: confusion-matrix
- **Description**: Confusion matrix for supervised classification
- **Primary Language**: Unknown
- **License**: MIT
- **Default Branch**: main
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-10-22
- **Last Updated**: 2026-07-26

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# confusion-matrix

[![NPM version][npm-image]][npm-url]
[![build status][ci-image]][ci-url]
[![npm download][download-image]][download-url]

Confusion matrix for supervised classification. Compute metrics on your classification like accuracy, sensitivity, specificity. The list of implemented metrics were inspired from [the confusion matrix wikipedia page](https://en.wikipedia.org/wiki/Confusion_matrix). See [API documentation](https://mljs.github.io/confusion-matrix/) for the list of metrics.

## Installation

`$ npm install --save ml-confusion-matrix`

## Usage

### Load the library

```js
// CommonJS
const { ConfusionMatrix } = require('ml-confusion-matrix');

// ES6 module syntax
import { ConfusionMatrix } from 'ml-confusion-matrix';
```

### Instanciate from the list of true and predicted labels

Handy if you want a confusion matrix from a cross-validation or from the test data set prediction results.

```js
const trueLabels = [0, 1, 0, 1, 1, 0];
const predictedLabels = [1, 1, 1, 1, 0, 0];

// The order of the arguments are important !!!
const CM2 = ConfusionMatrix.fromLabels(trueLabels, predictedLabels);
console.log(CM2.getAccuracy()); // 0.5
```

### Instanciate from confusion matrix

You can call the constructor directly with the confusion matrix and the labels corresponding to each rows/columns.

```js
const CM1 = new ConfusionMatrix(
  [
    [13, 2],
    [10, 5],
  ],
  ['cat', 'dog'],
);
console.log(CM1.getTruePositiveCount('cat')); // 13
```

## License

[MIT](./LICENSE)

[npm-image]: https://img.shields.io/npm/v/ml-confusion-matrix.svg?style=flat-square
[npm-url]: https://npmjs.org/package/ml-confusion-matrix
[ci-image]: https://github.com/mljs/confusion-matrix/workflows/Node.js%20CI/badge.svg?branch=main
[ci-url]: https://github.com/mljs/confusion-matrix/actions?query=workflow%3A%22Node.js+CI%22
[download-image]: https://img.shields.io/npm/dm/ml-confusion-matrix.svg?style=flat-square
[download-url]: https://npmjs.org/package/ml-confusion-matrix