Haversine calc in TypeScript

haversite.ts

export const haversine = (coordinates1: [number, number], coordinates2: [number, number]) => {

    const [ lat1, lon1 ] = coordinates1;
    const [ lat2, lon2 ] = coordinates2;
    const radian = (value: number) => value * (Math.PI / 180);

    const dLat = radian(lat2 - lat1);
    const dLon = radian(lon2 - lon1);

    const result = Math.sin(dLat / 2)
        * Math.sin(dLat / 2)
        + Math.cos(radian(lat1))
        * Math.cos(radian(lat2))
        * Math.sin(dLon / 2)
        * Math.sin(dLon / 2);

    return Math.floor((6371 * (2 * Math.atan2(Math.sqrt(result), Math.sqrt(1 - result)))) * 100) / 100;

};

Usage

const kmRatio = haversine([38.8976038, -77.036366], [55.753818, 37.6162696]); // 7821.84
console.info('From White House to Kremlin:', kmRatio);

Proof

https://www.movable-type.co.uk/scripts/latlong.html