How to use the @turf/helpers.degreesToRadians function in @turf/helpers

export default function destination<p>(
    origin: Coord,
    distance: number,
    bearing: number,
    options: {
        units?: Units,
        properties?: P,
    } = {},
): Feature {
    // Handle input
    const coordinates1 = getCoord(origin);
    const longitude1 = degreesToRadians(coordinates1[0]);
    const latitude1 = degreesToRadians(coordinates1[1]);
    const bearingRad = degreesToRadians(bearing);
    const radians = lengthToRadians(distance, options.units);

    // Main
    const latitude2 = Math.asin(Math.sin(latitude1) * Math.cos(radians) +
        Math.cos(latitude1) * Math.sin(radians) * Math.cos(bearingRad));
    const longitude2 = longitude1 + Math.atan2(Math.sin(bearingRad) * Math.sin(radians) * Math.cos(latitude1),
        Math.cos(radians) - Math.sin(latitude1) * Math.sin(latitude2));
    const lng = radiansToDegrees(longitude2);
    const lat = radiansToDegrees(latitude2);

    return point([lng, lat], options.properties);
}
</p>

function calculateRhumbBearing(from: number[], to: number[]) {
    // φ => phi
    // Δλ => deltaLambda
    // Δψ => deltaPsi
    // θ => theta
    const phi1 = degreesToRadians(from[1]);
    const phi2 = degreesToRadians(to[1]);
    let deltaLambda = degreesToRadians((to[0] - from[0]));
    // if deltaLambdaon over 180° take shorter rhumb line across the anti-meridian:
    if (deltaLambda > Math.PI) { deltaLambda -= 2 * Math.PI; }
    if (deltaLambda < -Math.PI) { deltaLambda += 2 * Math.PI; }

    const deltaPsi = Math.log(Math.tan(phi2 / 2 + Math.PI / 4) / Math.tan(phi1 / 2 + Math.PI / 4));

    const theta = Math.atan2(deltaLambda, deltaPsi);

    return (radiansToDegrees(theta) + 360) % 360;
}

export default function bearing(start: Coord, end: Coord, options: {
    final?: boolean,
} = {}): number {
    // Reverse calculation
    if (options.final === true) { return calculateFinalBearing(start, end); }

    const coordinates1 = getCoord(start);
    const coordinates2 = getCoord(end);

    const lon1 = degreesToRadians(coordinates1[0]);
    const lon2 = degreesToRadians(coordinates2[0]);
    const lat1 = degreesToRadians(coordinates1[1]);
    const lat2 = degreesToRadians(coordinates2[1]);
    const a = Math.sin(lon2 - lon1) * Math.cos(lat2);
    const b = Math.cos(lat1) * Math.sin(lat2) -
        Math.sin(lat1) * Math.cos(lat2) * Math.cos(lon2 - lon1);

    return radiansToDegrees(Math.atan2(a, b));
}

export default function bearing(start: Coord, end: Coord, options: {
    final?: boolean,
} = {}): number {
    // Reverse calculation
    if (options.final === true) { return calculateFinalBearing(start, end); }

    const coordinates1 = getCoord(start);
    const coordinates2 = getCoord(end);

    const lon1 = degreesToRadians(coordinates1[0]);
    const lon2 = degreesToRadians(coordinates2[0]);
    const lat1 = degreesToRadians(coordinates1[1]);
    const lat2 = degreesToRadians(coordinates2[1]);
    const a = Math.sin(lon2 - lon1) * Math.cos(lat2);
    const b = Math.cos(lat1) * Math.sin(lat2) -
        Math.sin(lat1) * Math.cos(lat2) * Math.cos(lon2 - lon1);

    return radiansToDegrees(Math.atan2(a, b));
}

function destination(origin, distance, bearing, options) {
    // Optional parameters
    options = options || {};
    if (!helpers.isObject(options)) throw new Error('options is invalid');
    var units = options.units;
    var properties = options.properties;

    // Handle input
    var coordinates1 = invariant.getCoord(origin);
    var longitude1 = helpers.degreesToRadians(coordinates1[0]);
    var latitude1 = helpers.degreesToRadians(coordinates1[1]);
    var bearing_rad = helpers.degreesToRadians(bearing);
    var radians = helpers.lengthToRadians(distance, units);

    // Main
    var latitude2 = Math.asin(Math.sin(latitude1) * Math.cos(radians) +
        Math.cos(latitude1) * Math.sin(radians) * Math.cos(bearing_rad));
    var longitude2 = longitude1 + Math.atan2(Math.sin(bearing_rad) * Math.sin(radians) * Math.cos(latitude1),
        Math.cos(radians) - Math.sin(latitude1) * Math.sin(latitude2));
    var lng = helpers.radiansToDegrees(longitude2);
    var lat = helpers.radiansToDegrees(latitude2);

    return helpers.point([lng, lat], properties);
}

function calculateRhumbBearing(from: number[], to: number[]) {
    // φ => phi
    // Δλ => deltaLambda
    // Δψ => deltaPsi
    // θ => theta
    const phi1 = degreesToRadians(from[1]);
    const phi2 = degreesToRadians(to[1]);
    let deltaLambda = degreesToRadians((to[0] - from[0]));
    // if deltaLambdaon over 180° take shorter rhumb line across the anti-meridian:
    if (deltaLambda > Math.PI) { deltaLambda -= 2 * Math.PI; }
    if (deltaLambda < -Math.PI) { deltaLambda += 2 * Math.PI; }

    const deltaPsi = Math.log(Math.tan(phi2 / 2 + Math.PI / 4) / Math.tan(phi1 / 2 + Math.PI / 4));

    const theta = Math.atan2(deltaLambda, deltaPsi);

    return (radiansToDegrees(theta) + 360) % 360;
}

export default function destination<p>(
    origin: Coord,
    distance: number,
    bearing: number,
    options: {
        units?: Units,
        properties?: P,
    } = {},
): Feature {
    // Handle input
    const coordinates1 = getCoord(origin);
    const longitude1 = degreesToRadians(coordinates1[0]);
    const latitude1 = degreesToRadians(coordinates1[1]);
    const bearingRad = degreesToRadians(bearing);
    const radians = lengthToRadians(distance, options.units);

    // Main
    const latitude2 = Math.asin(Math.sin(latitude1) * Math.cos(radians) +
        Math.cos(latitude1) * Math.sin(radians) * Math.cos(bearingRad));
    const longitude2 = longitude1 + Math.atan2(Math.sin(bearingRad) * Math.sin(radians) * Math.cos(latitude1),
        Math.cos(radians) - Math.sin(latitude1) * Math.sin(latitude2));
    const lng = radiansToDegrees(longitude2);
    const lat = radiansToDegrees(latitude2);

    return point([lng, lat], options.properties);
}
</p>

function calculateRhumbDestination(origin: number[], distance: number, bearing: number, radius?: number) {
    // φ => phi
    // λ => lambda
    // ψ => psi
    // Δ => Delta
    // δ => delta
    // θ => theta

    radius = (radius === undefined) ? earthRadius : Number(radius);

    const delta = distance / radius; // angular distance in radians
    const lambda1 = origin[0] * Math.PI / 180; // to radians, but without normalize to 𝜋
    const phi1 = degreesToRadians(origin[1]);
    const theta = degreesToRadians(bearing);

    const DeltaPhi = delta * Math.cos(theta);
    let phi2 = phi1 + DeltaPhi;

    // check for some daft bugger going past the pole, normalise latitude if so
    if (Math.abs(phi2) > Math.PI / 2) { phi2 = phi2 > 0 ? Math.PI - phi2 : -Math.PI - phi2; }

    const DeltaPsi = Math.log(Math.tan(phi2 / 2 + Math.PI / 4) / Math.tan(phi1 / 2 + Math.PI / 4));
    // E-W course becomes ill-conditioned with 0/0
    const q = Math.abs(DeltaPsi) > 10e-12 ? DeltaPhi / DeltaPsi : Math.cos(phi1);

    const DeltaLambda = delta * Math.sin(theta) / q;
    const lambda2 = lambda1 + DeltaLambda;

    return [((lambda2 * 180 / Math.PI) + 540) % 360 - 180, phi2 * 180 / Math.PI]; // normalise to −180..+180°
}

export function lnglatDistance(
  coordinates1: [number, number],
  coordinates2: [number, number],
  units?: Units,
): number {
  const dLat = degreesToRadians(coordinates2[1] - coordinates1[1]);
  const dLon = degreesToRadians(coordinates2[0] - coordinates1[0]);
  const lat1 = degreesToRadians(coordinates1[1]);
  const lat2 = degreesToRadians(coordinates2[1]);
  const a =
    Math.pow(Math.sin(dLat / 2), 2) +
    Math.pow(Math.sin(dLon / 2), 2) * Math.cos(lat1) * Math.cos(lat2);

  return radiansToLength(
    2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a)),
    (units = 'meters'),
  );
}