function containsNumber(coordinates) {
    if (coordinates.length > 1 &&
        helpers_1.isNumber(coordinates[0]) &&
        helpers_1.isNumber(coordinates[1])) {
        return true;
    }
    if (Array.isArray(coordinates[0]) && coordinates[0].length) {
        return containsNumber(coordinates[0]);
    }
    throw new Error("coordinates must only contain numbers");
}
Checks if coordinates contains a number

@name containsNumber
@param {Array<any>} coordinates GeoJSON Coordinates
@returns {boolean} true if Array contains a number