The aim of this puzzle: Complete the averageRating()
function definition so that it returns the average rating for a list of hotels. Then find the average rating for Hoptropolis hotels.
Walkthrough of the solution: The average()
and getRatings()
functions that you created in the previous puzzles are imported so that you can use them here.
The averageRating()
function definition will take a list of reviews stored in hotelList
. Then it uses the getRatings()
function to get an array of just the ratings of those hotels and stores it in ratings
. To calculate the average of the ratings
, you can use your average()
function. Instead of returning 0, the function should return average(ratings)
.
The hoptropolisHotels
variable is storing an array of all the hotels in Hoptropolis. To get the average rating, you can use averageRating(hoptropolisHotels)
. In order to see the output of that call, you need to use a console.log()
. That whole command should go at the bottom of your code.
Sample code solution:
(Tap below to reveal)
import { getData, findHotels } from 'grasshopper.reviews';
import { average, getRatings } from 'myFunctions';
function averageRating(hotelList) {
let ratings = getRatings(hotelList);
return average(ratings);
}
let grasslandHotels = getData('Grassland', findHotels);
console.log('Average Grassland hotel rating:');
console.log(averageRating(grasslandHotels));
let hoptropolisHotels = getData('Hoptropolis', findHotels);
console.log('Average Hoptropolis hotel rating:');
console.log(averageRating(hoptropolisHotels));
JavaScript Concepts: Callback Functions, Calling Functions, Code Block (function), import
Additional Code (hidden code that runs before the puzzleâs code):
let _hotelReviews = [
{
type: 'Hopaday Inn',
city: 'Hopalot',
price: 138,
rating: 4.0
},
{
type: 'Hopaday Inn',
city: 'Hopalot',
price: 78,
rating: 3.8
},
{
type: 'Hopaday Inn',
city: 'Hoptropolis',
price: 86,
rating: 2.4
},
{
type: 'Hopaday Inn',
city: 'Hoptropolis',
price: 126,
rating: 4.4
},
{
type: 'Hopaday Inn',
city: 'Grassland',
price: 138,
rating: 3.0
},
{
type: 'Hopaday Inn',
city: 'Grassland',
price: 245,
rating: 4.6
},
{
type: 'The Grassy Suites',
city: 'Hopalot',
price: 189,
rating: 4.4
},
{
type: 'The Grassy Suites',
city: 'Hopalot',
price: 111,
rating: 2.4
},
{
type: 'The Grassy Suites',
city: 'Hoptropolis',
price: 171,
rating: 2.8
},
{
type: 'The Grassy Suites',
city: 'Hoptropolis',
price: 191,
rating: 2.8
},
{
type: 'The Grassy Suites',
city: 'Grassland',
price: 265,
rating: 4.1
},
{
type: 'The Grassy Suites',
city: 'Grassland',
price: 186,
rating: 3.5
},
{
type: 'Hopton Inn',
city: 'Hopalot',
price: 160,
rating: 2.4
},
{
type: 'Hopton Inn',
city: 'Hoptropolis',
price: 226,
rating: 4.5
},
{
type: 'Hopton Inn',
city: 'Hoptropolis',
price: 192,
rating: 3.5
},
{
type: 'Hopton Inn',
city: 'Grassland',
price: 149,
rating: 4.9
}
];
const getData = (city, afunction) => {
afunction(city.trim().charAt(0).toUpperCase() + city.trim().toLowerCase().slice(1));
};
const findHotels = city => {
_hotelReviews.filter( review => review.city === city);
};
const average = array => {
array.reduce((a, b) => a + b) / array.length
};
const getRatings = hotelList => {
hotelList.map(hotel => hotel.rating)
};