# @hamset/maidenhead-locator

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Maidenhead grid locator and WGS84 coordinate calculation and transformation

## Usage

```bash
npm i @hamset/maidenhead-locator
```

```typescript
import {
  validateGridLocator,
  WGS84ToMaidenhead,
  maidenheadToWGS84,
  maidenheadToBoundingBox,
  GridLocator,
  WGS84,
  LatLng
} from '@hamset/maidenhead-locator';

// convert maidenhead grid locator to WGS84 coordinate
const grid_locator = 'DM06gs'
const coordinate: WGS84 = maidenheadToWGS84(grid_locator);
// output: { lat: 36.75, lng: -119.5 }

// convert WGS84 coordinate to maidenhead grid locator
const coordinate: LatLng = { lat: 36.75, lng: -119.5 }
const grid_locator: GridLocator = WGS84ToMaidenhead(coordinate);
// output: 'DM06gs'

// get bounding box coordinates from maidenhead grid locator
const grid_locator = 'DM06gs'
const bounds: [LatLng, LatLng] = maidenheadToBoundingBox(grid_locator); 
// output: [ [ 36.75, -119.5 ], [ 36.791666666666664, -119.41666666666667 ] ]
```

## APIs

```typescript
import { CoordinateLike, GridLocator, WGS84 } from "./types";
/**
 * Validate grid locator
 * @param gridLocator grid locator
 * @returns true if the grid locator is valid
 */
declare const validateGridLocator: (gridLocator: GridLocator) => boolean;
/**
 * Convert WGS84 to Maidenhead
 * @param coord coordinate
 * @returns grid locator
 */
declare const WGS84ToMaidenhead: (coord: CoordinateLike) => GridLocator;
/**
 * Convert Maidenhead to WGS84
 * @param gridLocator grid locator
 * @returns coordinate
 */
declare const maidenheadToWGS84: (gridLocator: GridLocator) => WGS84;
/**
 * Convert Maidenhead to bounding box coordinates
 * @param gridLocator grid locator
 * @returns A two-dimensional array containing two diagonal coordinates of bounds
 */
declare const maidenheadToBoundingBox: (gridLocator: GridLocator) => [LatLng, LatLng];

//
// types
//
export type LatLng = [number, number];
export interface WGS84 {
    lat: number;
    lng: number;
}
export type CoordinateLike = LatLng | WGS84;
export type LatLngBounds = [LatLng, LatLng];
export type GridLocator = string;
```