### Install geo-polyline-tools with npm

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Use npm to install the library. This is the standard package manager for Node.js.

```bash
npm install geo-polyline-tools
```

--------------------------------

### Initialize Project Environment

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/DEVELOPMENT.md

Commands to clone the repository and install necessary dependencies.

```bash
git clone https://github.com/barikoi/geo-polyline-tools.git
cd geo-polyline-tools
npm install
```

--------------------------------

### Initialize Development Environment

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/CONTRIBUTING.md

Commands to clone the repository and install dependencies.

```bash
git clone https://github.com/<your-username>/geo-polyline-tools.git
cd geo-polyline-tools
npm install
git checkout -b feature/my-change
```

```bash
git clone https://github.com/barikoi/geo-polyline-tools.git
cd geo-polyline-tools
npm install
```

--------------------------------

### TypeScript Usage Example

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Example of importing and using the library in a TypeScript project, demonstrating type safety.

```typescript
import polyline from 'geo-polyline-tools';

const encoded: string = polyline.encode([[38.5, -120.2], [40.7, -120.95]], 5);
```

--------------------------------

### Install geo-polyline-tools with yarn

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Use yarn to install the library. Yarn is an alternative package manager for Node.js.

```bash
yarn add geo-polyline-tools
```

--------------------------------

### Package Testing with Tarball

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/CONTRIBUTING.md

Steps to build, pack, and install the package locally for verification.

```bash
# 1. Build the project
npm run build

# 2. Generate a tarball
npm pack

# 3. Install the tarball in a test project
mkdir /tmp/test-polyline && cd /tmp/test-polyline
npm init -y
npm install /path/to/geo-polyline-tools/geo-polyline-tools-1.0.6.tgz
```

--------------------------------

### Conventional Commit Examples

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/CONTRIBUTING.md

Examples of commit messages following the conventional commits specification for various project scopes.

```text
feat(geojson): add support for MultiLineString geometries
fix(decode): handle empty string input without error
docs: update coordinate ordering table in README
refactor(encode): simplify py2_round implementation
test(decode): add edge case tests for high-precision coordinates
chore(build): upgrade rollup to v4.60
types: mark precision parameter as optional
```

--------------------------------

### Browser IIFE Usage Example

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Example of using the library in a browser after including it via an IIFE script tag. The library is accessed via the global `geoPolylineTools` object.

```javascript
var encoded = geoPolylineTools.encode([[38.5, -120.2], [40.7, -120.95], [43.252, -126.453]], 5);
console.log(encoded); // '_p~iF~ps|U_ulLnnqC_mqNvxq`@'
```

--------------------------------

### Publishing Workflow

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/DEVELOPMENT.md

Steps to version, validate, and publish the package to NPM.

```bash
# 1. Update version in package.json
npm version patch   # or minor, or major

# 2. Run the full validation
npm run lint && npm test && npm run build

# 3. Publish to npm
npm publish
```

--------------------------------

### Build Project

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/DEVELOPMENT.md

Command to trigger the build process using Rollup.

```bash
npm run build
```

--------------------------------

### Package Publishing Workflow

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/CONTRIBUTING.md

Commands for versioning, validating, and publishing the package to the npm registry.

```bash
# 1. Update the version
npm version patch   # for bug fixes: 1.0.6 -> 1.0.7
npm version minor   # for new features: 1.0.6 -> 1.1.0
npm version major   # for breaking changes: 1.0.6 -> 2.0.0

# 2. Run full validation
npm run lint && npm test && npm run build

# 3. Publish to npm (package is configured as public in publishConfig)
npm publish

# 4. Push the version tag to GitHub
git push origin main --follow-tags
```

--------------------------------

### Run Test Suite

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/DEVELOPMENT.md

Command to execute all tests using Jest.

```bash
# Run all tests
npm test
```

--------------------------------

### Project Structure

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/CONTRIBUTING.md

Overview of the directory layout for the project.

```text
geo-polyline-tools/
├── src/
│   └── index.ts          # Library source code (encode, decode, GeoJSON helpers)
├── types/
│   └── index.d.ts        # Manual type declarations (NOT auto-generated)
├── __tests__/
│   └── index.test.ts     # Jest test suite
├── dist/                  # Build output (generated, do not edit)
│   ├── cjs/               # CommonJS bundle (index.cjs)
│   ├── esm/               # ES Module bundle (index.js)
│   └── iife/              # Browser IIFE bundle (geo-polyline-tools.js)
├── package.json
├── tsconfig.json
├── rollup.config.js
├── jest.config.cjs
└── .eslintrc.json
```

--------------------------------

### Package Quality Tools

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/CONTRIBUTING.md

Commands to validate package configuration and type resolution.

```bash
npx publint                        # Check package configuration
npx @arethetypeswrong/cli --pack . # Verify TypeScript type resolution
```

--------------------------------

### Project Directory Structure

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/DEVELOPMENT.md

Visual representation of the project file layout.

```text
geo-polyline-tools/
├── src/
│   └── index.ts          # Library source code
├── types/
│   └── index.d.ts        # Manual type declarations
├── __tests__/
│   └── index.test.ts     # Test suite
├── dist/                  # Build output (generated)
│   ├── cjs/               # CommonJS bundle
│   ├── esm/               # ES Module bundle
│   └── iife/              # Browser IIFE bundle
├── package.json
├── tsconfig.json
├── rollup.config.js
├── jest.config.cjs
└── .eslintrc.json
```

--------------------------------

### Run Tests

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/CONTRIBUTING.md

Execute the Jest test suite.

```bash
npm test
```

--------------------------------

### Verify Module Formats

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/CONTRIBUTING.md

Test the package using CommonJS and ESM imports.

```javascript
// CommonJS
const polyline = require('geo-polyline-tools');
console.log(polyline.encode([[38.5, -120.2]], 5));
```

```javascript
// ESM
import polyline from 'geo-polyline-tools';
console.log(polyline.decode('_p~iF~ps|U_ulLnnqC_mqNvxq`@', 5));
```

--------------------------------

### Include geo-polyline-tools in Browser (IIFE)

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Include the library directly in your HTML using a script tag, either locally or via a CDN. This makes the library available globally.

```html
<!-- Local -->
<script src="node_modules/geo-polyline-tools/dist/iife/geo-polyline-tools.js"></script>

<!-- unpkg CDN -->
<script src="https://unpkg.com/geo-polyline-tools@latest/dist/iife/geo-polyline-tools.js"></script>

<!-- jsdelivr CDN -->
<script src="https://cdn.jsdelivr.net/npm/geo-polyline-tools@latest/dist/iife/geo-polyline-tools.js"></script>
```

--------------------------------

### Validate Package Quality

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/DEVELOPMENT.md

Commands to verify package configuration and TypeScript types before publishing.

```bash
npx publint                           # Check package configuration
npx @arethetypeswrong/cli --pack .    # Verify TypeScript types
npm run build                         # Build the project
npm pack                              # Generate tarball
```

--------------------------------

### Lint Source Code

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/DEVELOPMENT.md

Command to run ESLint for code style validation.

```bash
npm run lint
```

--------------------------------

### Import geo-polyline-tools in ES Module

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Import the library using ES Module syntax. This is common in modern JavaScript projects.

```javascript
import polyline from 'geo-polyline-tools';
```

--------------------------------

### Import geo-polyline-tools in CommonJS

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Import the library using CommonJS syntax. This is typically used in Node.js environments.

```javascript
const polyline = require('geo-polyline-tools');
```

--------------------------------

### Conventional Commit Format

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/CONTRIBUTING.md

Standard structure for commit messages.

```text
<type>(<scope>): <description>

[optional body]

[optional footer(s)]
```

--------------------------------

### Encode Coordinates to Polyline String

Source: https://context7.com/barikoi/geo-polyline-tools/llms.txt

Converts an array of [latitude, longitude] pairs into a compressed polyline string. Supports custom precision; default is 5 decimal places.

```javascript
import polyline from 'geo-polyline-tools';

// Encode a route with three waypoints
const coordinates = [
  [38.5, -120.2],
  [40.7, -120.95],
  [43.252, -126.453]
];

const encoded = polyline.encode(coordinates, 5);
console.log(encoded);
// Output: '_p~iF~ps|U_ulLnnqC_mqNvxq`@'

// Encode with higher precision (6 decimal places)
const highPrecisionEncoded = polyline.encode(coordinates, 6);
console.log(highPrecisionEncoded);
// Output: 'o}oia@~bkbK_seK~nskB_ibO`reaE'

// Handle empty coordinates gracefully
const emptyResult = polyline.encode([], 5);
console.log(emptyResult);
// Output: ''
```

--------------------------------

### Decode Polyline String to Coordinates

Source: https://context7.com/barikoi/geo-polyline-tools/llms.txt

Decodes a polyline string back into an array of [latitude, longitude] pairs. The precision parameter must match the encoding precision.

```javascript
import polyline from 'geo-polyline-tools';

// Decode a polyline string to coordinates
const polylineString = '_p~iF~ps|U_ulLnnqC_mqNvxq`@';
const coordinates = polyline.decode(polylineString, 5);

console.log(coordinates);
// Output: [[38.5, -120.2], [40.7, -120.95], [43.252, -126.453]]

// Access individual coordinate points
coordinates.forEach((coord, index) => {
  const [latitude, longitude] = coord;
  console.log(`Point ${index + 1}: lat=${latitude}, lng=${longitude}`);
});
// Output:
// Point 1: lat=38.5, lng=-120.2
// Point 2: lat=40.7, lng=-120.95
// Point 3: lat=43.252, lng=-126.453

// Handle empty polyline string
const emptyCoords = polyline.decode('', 5);
console.log(emptyCoords);
// Output: []
```

--------------------------------

### polyline.encode

Source: https://context7.com/barikoi/geo-polyline-tools/llms.txt

Converts an array of [latitude, longitude] coordinate pairs into a compressed polyline string. Supports configurable precision.

```APIDOC
## polyline.encode

### Description
Converts an array of [latitude, longitude] coordinate pairs into a compressed polyline string using Google's Encoded Polyline Algorithm. The precision parameter controls the number of decimal places preserved in the encoding, with a default of 5 (approximately 1.1 meter accuracy).

### Method
`encode(coordinates: Array<[number, number]>, precision?: number): string`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```javascript
import polyline from 'geo-polyline-tools';

const coordinates = [
  [38.5, -120.2],
  [40.7, -120.95],
  [43.252, -126.453]
];

const encoded = polyline.encode(coordinates, 5);
console.log(encoded);
// Output: '_p~iF~ps|U_ulLnnqC_mqNvxq`@'
```

### Response
#### Success Response (200)
- **encoded_string** (string) - The compressed polyline string.

#### Response Example
```json
{
  "encoded_string": "_p~iF~ps|U_ulLnnqC_mqNvxq`@"
}
```
```

--------------------------------

### polyline.decode

Source: https://context7.com/barikoi/geo-polyline-tools/llms.txt

Decodes a polyline string back into an array of [latitude, longitude] coordinate pairs. The precision must match the encoding precision.

```APIDOC
## polyline.decode

### Description
Decodes a polyline string back into an array of [latitude, longitude] coordinate pairs. The precision parameter must match the precision used during encoding to correctly reconstruct the original coordinates.

### Method
`decode(encoded_string: string, precision?: number): Array<[number, number]>`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```javascript
import polyline from 'geo-polyline-tools';

const polylineString = '_p~iF~ps|U_ulLnnqC_mqNvxq`@';
const coordinates = polyline.decode(polylineString, 5);

console.log(coordinates);
// Output: [[38.5, -120.2], [40.7, -120.95], [43.252, -126.453]]
```

### Response
#### Success Response (200)
- **coordinates** (Array<[number, number]>) - An array of [latitude, longitude] coordinate pairs.

#### Response Example
```json
{
  "coordinates": [
    [38.5, -120.2],
    [40.7, -120.95],
    [43.252, -126.453]
  ]
}
```
```

--------------------------------

### Convert Polyline String to GeoJSON LineString

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Decode a compressed polyline string into a GeoJSON `LineString` geometry object. The library automatically handles the `[latitude, longitude]` to `[longitude, latitude]` axis conversion.

```javascript
const str = '_p~iF~ps|U_ulLnnqC_mqNvxq`@';

const geometry = polyline.toGeoJSON(str, 5);
// => {
//      type: 'LineString',
//      coordinates: [[-120.2, 38.5], [-120.95, 40.7], [-126.453, 43.252]]
//    }
```

--------------------------------

### polyline.encode

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Encodes an array of [latitude, longitude] coordinate pairs into a polyline string.

```APIDOC
## polyline.encode(coordinates, precision?)

### Description
Encodes an array of [latitude, longitude] coordinate pairs into a polyline string.

### Parameters
#### Arguments
- **coordinates** (number[][]) - Required - Array of [lat, lng] pairs.
- **precision** (number) - Optional - Number of decimal places to preserve (Default: 5).

### Returns
- **string** - The encoded polyline. Returns an empty string when coordinates is empty.
```

--------------------------------

### Convert GeoJSON LineString to Polyline

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Encode a GeoJSON Feature with a `LineString` geometry into a compressed polyline string. The library automatically handles the `[longitude, latitude]` to `[latitude, longitude]` axis conversion.

```javascript
const geojson = {
  type: 'Feature',
  geometry: {
    type: 'LineString',
    coordinates: [[38.5, -120.2], [40.7, -120.95], [43.252, -126.453]],
  },
};

const encoded = polyline.fromGeoJSON(geojson, 5);
// => '~ps|U_p~iFnnqC_ulLvxq`@_mqN'
```

--------------------------------

### Decode polyline to GeoJSON

Source: https://context7.com/barikoi/geo-polyline-tools/llms.txt

Converts a polyline string into a GeoJSON LineString object and demonstrates wrapping it in a FeatureCollection for mapping libraries.

```javascript
import polyline from 'geo-polyline-tools';

// Decode polyline to GeoJSON LineString
const polylineString = '_p~iF~ps|U_ulLnnqC_mqNvxq`@';
const geoJson = polyline.toGeoJSON(polylineString, 5);

console.log(JSON.stringify(geoJson, null, 2));
// Output:
// {
//   "type": "LineString",
//   "coordinates": [
//     [-120.2, 38.5],
//     [-120.95, 40.7],
//     [-126.453, 43.252]
//   ]
// }

// Use with mapping libraries (example with Leaflet-style usage)
const routeData = polyline.toGeoJSON('_p~iF~ps|U_ulLnnqC_mqNvxq`@', 5);
const featureCollection = {
  type: 'FeatureCollection',
  features: [{
    type: 'Feature',
    properties: { name: 'Decoded Route' },
    geometry: routeData
  }]
};

console.log(JSON.stringify(featureCollection, null, 2));
// Ready for use with GeoJSON-compatible mapping libraries
```

--------------------------------

### polyline.toGeoJSON

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Decodes a polyline string into a GeoJSON LineString geometry object.

```APIDOC
## polyline.toGeoJSON(str, precision?)

### Description
Decodes a polyline string into a GeoJSON LineString geometry object. The resulting coordinates follow GeoJSON's [longitude, latitude] ordering.

### Parameters
#### Arguments
- **str** (string) - Required - The encoded polyline string.
- **precision** (number) - Optional - Number of decimal places used during encoding (Default: 5).

### Returns
- **{ type: 'LineString', coordinates: number[][] }** - A GeoJSON LineString geometry with [lng, lat] coordinates.
```

--------------------------------

### polyline.toGeoJSON

Source: https://context7.com/barikoi/geo-polyline-tools/llms.txt

Decodes a polyline string into a GeoJSON LineString geometry object. The resulting coordinates are in GeoJSON standard order [longitude, latitude], ready for use with mapping libraries like Leaflet, Mapbox, or OpenLayers.

```APIDOC
## polyline.toGeoJSON

### Description
Decodes a polyline string into a GeoJSON LineString geometry object. The resulting coordinates are in GeoJSON standard order [longitude, latitude], ready for use with mapping libraries like Leaflet, Mapbox, or OpenLayers.

### Method
`polyline.toGeoJSON(encodedPolyline, precision)`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```javascript
import polyline from 'geo-polyline-tools';

// Decode polyline to GeoJSON LineString
const polylineString = '_p~iF~ps|U_ulLnnqC_mqNvxq`@';
const geoJson = polyline.toGeoJSON(polylineString, 5);

console.log(JSON.stringify(geoJson, null, 2));
```

### Response
#### Success Response (200)
- **type** (string) - The geometry type, always "LineString".
- **coordinates** (array) - An array of coordinate pairs, where each pair is [longitude, latitude].

#### Response Example
```json
{
  "type": "LineString",
  "coordinates": [
    [-120.2, 38.5],
    [-120.95, 40.7],
    [-126.453, 43.252]
  ]
}
```

### Additional Usage Examples
```javascript
// Use with mapping libraries (example with Leaflet-style usage)
const routeData = polyline.toGeoJSON('_p~iF~ps|U_ulLnnqC_mqNvxq`@', 5);
const featureCollection = {
  type: 'FeatureCollection',
  features: [{
    type: 'Feature',
    properties: { name: 'Decoded Route' },
    geometry: routeData
  }]
};

console.log(JSON.stringify(featureCollection, null, 2));
// Ready for use with GeoJSON-compatible mapping libraries
```
```

--------------------------------

### polyline.toGeoJSON

Source: https://context7.com/barikoi/geo-polyline-tools/llms.txt

Decodes a polyline string into a GeoJSON LineString geometry, handling coordinate order conversion.

```APIDOC
## polyline.toGeoJSON

### Description
Decodes a polyline string into a GeoJSON LineString geometry. This function automatically handles the coordinate order conversion between polyline format ([latitude, longitude]) and GeoJSON ([longitude, latitude]).

### Method
`toGeoJSON(encoded_string: string, precision?: number): object`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```javascript
import polyline from 'geo-polyline-tools';

const encodedPolyline = '_p~iF~ps|U_ulLnnqC_mqNvxq`@';
const geoJsonLineString = polyline.toGeoJSON(encodedPolyline, 5);

console.log(JSON.stringify(geoJsonLineString, null, 2));
/*
Output:
{
  "type": "LineString",
  "coordinates": [
    [-120.2, 38.5],
    [-120.95, 40.7],
    [-126.453, 43.252]
  ]
}
*/
```

### Response
#### Success Response (200)
- **geoJson** (object) - A GeoJSON LineString geometry object.

#### Response Example
```json
{
  "type": "LineString",
  "coordinates": [
    [-120.2, 38.5],
    [-120.95, 40.7],
    [-126.453, 43.252]
  ]
}
```
```

--------------------------------

### polyline.fromGeoJSON

Source: https://github.com/barikoi/geo-polyline-tools/blob/main/README.md

Encodes a GeoJSON Feature or LineString geometry into a polyline string.

```APIDOC
## polyline.fromGeoJSON(geojson, precision?)

### Description
Encodes a GeoJSON Feature or LineString geometry into a polyline string. Coordinates are expected in GeoJSON [longitude, latitude] ordering and are internally flipped to [latitude, longitude] before encoding.

### Parameters
#### Arguments
- **geojson** (object) - Required - A GeoJSON Feature with LineString geometry, or a LineString geometry directly.
- **precision** (number) - Optional - Number of decimal places to preserve (Default: 5).

### Returns
- **string** - The encoded polyline.

### Errors
- Throws Error('Input must be a GeoJSON LineString') if the input is not a valid GeoJSON LineString or Feature containing one.
```

--------------------------------

### polyline.fromGeoJSON

Source: https://context7.com/barikoi/geo-polyline-tools/llms.txt

Encodes a GeoJSON Feature or LineString geometry into a polyline string, handling coordinate order conversion.

```APIDOC
## polyline.fromGeoJSON

### Description
Encodes a GeoJSON Feature or LineString geometry into a polyline string. This function automatically handles the coordinate order conversion between GeoJSON ([longitude, latitude]) and polyline format ([latitude, longitude]).

### Method
`fromGeoJSON(geoJson: object, precision?: number): string`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
- **geoJson** (object) - Required - A GeoJSON Feature or LineString geometry object.
- **precision** (number) - Optional - The precision level for encoding (default is 5).

### Request Example
```javascript
import polyline from 'geo-polyline-tools';

const geoJsonFeature = {
  type: 'Feature',
  properties: { name: 'Sample Route' },
  geometry: {
    type: 'LineString',
    coordinates: [
      [38.5, -120.2],
      [40.7, -120.95],
      [43.252, -126.453]
    ]
  }
};

const encoded = polyline.fromGeoJSON(geoJsonFeature, 5);
console.log(encoded);
// Output: '~ps|U_p~iFnnqC_ulLvxq`@_mqN'
```

### Response
#### Success Response (200)
- **encoded_string** (string) - The compressed polyline string.

#### Response Example
```json
{
  "encoded_string": "~ps|U_p~iFnnqC_ulLvxq`@_mqN"
}
```
```

--------------------------------

### Encode GeoJSON to Polyline String

Source: https://context7.com/barikoi/geo-polyline-tools/llms.txt

Encodes a GeoJSON Feature or LineString geometry into a polyline string. Automatically handles coordinate order conversion.

```javascript
import polyline from 'geo-polyline-tools';

// Convert a GeoJSON Feature to polyline
const geoJsonFeature = {
  type: 'Feature',
  properties: { name: 'Sample Route' },
  geometry: {
    type: 'LineString',
    coordinates: [
      [38.5, -120.2],
      [40.7, -120.95],
      [43.252, -126.453]
    ]
  }
};

const encoded = polyline.fromGeoJSON(geoJsonFeature, 5);
console.log(encoded);
// Output: '~ps|U_p~iFnnqC_ulLvxq`@_mqN'

// Convert a GeoJSON LineString geometry directly
const lineStringGeometry = {
  type: 'LineString',
  coordinates: [
    [-122.4194, 37.7749],  // San Francisco
    [-118.2437, 34.0522],  // Los Angeles
    [-117.1611, 32.7157]   // San Diego
  ]
};

const routePolyline = polyline.fromGeoJSON(lineStringGeometry, 5);
console.log(routePolyline);

// Error handling for invalid input
try {
  const invalidGeoJson = { type: 'Feature' }; // Missing geometry
  polyline.fromGeoJSON(invalidGeoJson, 5);
} catch (error) {
  console.error(error.message);
  // Output: 'Input must be a GeoJSON LineString'
}
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.