Incorporating an element into a nested array

Question

Incorporating an element into a nested array

I have an array stored in a variable called 'items' with various products and their attributes. I am looking to randomly generate a popularity score between 1 and 100 for the items that currently do not have one.

This is my current array:

const items = [  
     {name: "tablet", description: "12inch", price: 700, popularity: 99},   
     {name: "phone", description: "8inch", price: 900},  
     {name: "computer", description: "32inch", price: 3000, popularity: 50},  
     {name: "laptop", dimensions: "17inch", price: 1500},             
];

Here is the code snippet I am using:

for (var n = 0; n < 3; ++n) {           
    if (typeof items[n].popularity === 'undefined') {  
        var randomNum = Math.floor(Math.random() * 100);  
        items[n].popularity = randomNum;   
    }
}

When I console.log the array, I get the desired result:

{name: "tablet", description: "12inch", price: 700, popularity: 99},   
{name: "phone", description: "8inch", price: 900, popularity: 51},   
{name: "computer", description: "32inch", price: 3000, popularity: 50},   
{name: "laptop", dimensions: "17inch", price: 1500, popularity: 32},

Any suggestions on how I can improve this code are welcome. Thank you!

javascript arrays push

Answer 1

Answer №1

To solve this issue, you can iterate through the items and include the missing field if it's not already there:

const items = [
    { name: 'tablet', description: '12inch', price: 700, popularity: 99 },
    { name: 'phone', description: '8inch', price: 900 },
    { name: 'computer', description: '32inch', price: 3000, popularity: 50 },
    { name: 'laptop', dimensions: '17inch', price: 1500 },
];

items.forEach(i => i.popularity = i.popularity || Math.ceil(Math.random() * 100));

console.log(items);

It's recommended to use Math.ceil() rather than Math.floor() since you specified a value between 1 and 100.

Answer 2

To solve this issue, you can iterate through the items and include the missing field if it's not already there:

const items = [
    { name: 'tablet', description: '12inch', price: 700, popularity: 99 },
    { name: 'phone', description: '8inch', price: 900 },
    { name: 'computer', description: '32inch', price: 3000, popularity: 50 },
    { name: 'laptop', dimensions: '17inch', price: 1500 },
];

items.forEach(i => i.popularity = i.popularity || Math.ceil(Math.random() * 100));

console.log(items);

It's recommended to use Math.ceil() rather than Math.floor() since you specified a value between 1 and 100.

Answer 3

Answer №2

If you're looking to transform an array in JavaScript, consider using the map() method.

const items = [
    { name: 'tablet', description: '12inch', price: 700, popularity: 99 },
    { name: 'phone', description: '8inch', price: 900 },
    { name: 'computer', description: '32inch', price: 3000, popularity: 50 },
    { name: 'laptop', dimensions: '17inch', price: 1500 },
];

const result = items.map(item => (item.popularity ? item : { ...item, popularity: Math.floor(Math.random() * 100) }));

console.log(result);

Answer 4

If you're looking to transform an array in JavaScript, consider using the map() method.

const items = [
    { name: 'tablet', description: '12inch', price: 700, popularity: 99 },
    { name: 'phone', description: '8inch', price: 900 },
    { name: 'computer', description: '32inch', price: 3000, popularity: 50 },
    { name: 'laptop', dimensions: '17inch', price: 1500 },
];

const result = items.map(item => (item.popularity ? item : { ...item, popularity: Math.floor(Math.random() * 100) }));

console.log(result);

Answer 5

Answer №3

Your code if ([6 == 'undefined']) - It's not a syntax error, but rather a complete logical error. It equates to if ([false]) because the two constants are not the same, ultimately resulting in if (true) since it's a non-empty array.

There are more efficient ways to achieve this, with the best approach being to use the Array.map() function:

const items = [{
    name: 'tablet',
    description: '12inch',
    price: 700,
    popularity: 99
  },
  {
    name: 'phone',
    description: '8inch',
    price: 900
  },
  {
    name: 'computer',
    description: '32inch',
    price: 3000,
    popularity: 50
  },
  {
    name: 'laptop',
    dimensions: '17inch',
    price: 1500
  },
];

const result = items.map(item => (item.popularity ? item : { ...item,
  popularity: Math.floor(Math.random() * 100)
}));

console.log(result);

Answer 6

Your code if ([6 == 'undefined']) - It's not a syntax error, but rather a complete logical error. It equates to if ([false]) because the two constants are not the same, ultimately resulting in if (true) since it's a non-empty array.

There are more efficient ways to achieve this, with the best approach being to use the Array.map() function:

const items = [{
    name: 'tablet',
    description: '12inch',
    price: 700,
    popularity: 99
  },
  {
    name: 'phone',
    description: '8inch',
    price: 900
  },
  {
    name: 'computer',
    description: '32inch',
    price: 3000,
    popularity: 50
  },
  {
    name: 'laptop',
    dimensions: '17inch',
    price: 1500
  },
];

const result = items.map(item => (item.popularity ? item : { ...item,
  popularity: Math.floor(Math.random() * 100)
}));

console.log(result);

Answer 7

Answer №4

Implementing map alongside the nullish coalescing operator (??) can be powerful

const products = [
  { name: "tablet", description: "12inch", price: 700, popularity: 99 },
  { name: "phone", description: "8inch", price: 900 },
  { name: "computer", description: "32inch", price: 3000, popularity: 50 },
  { name: "laptop", dimensions: "17inch", price: 1500 },
];

const updateProducts = (arr) =>
  arr.map(({ popularity, ...item }) => ({
    popularity: popularity ?? Math.floor(Math.random() * 100) + 1,
    ...item,
  }));

console.log(updateProducts(products));

Answer 8

Implementing map alongside the nullish coalescing operator (??) can be powerful

const products = [
  { name: "tablet", description: "12inch", price: 700, popularity: 99 },
  { name: "phone", description: "8inch", price: 900 },
  { name: "computer", description: "32inch", price: 3000, popularity: 50 },
  { name: "laptop", dimensions: "17inch", price: 1500 },
];

const updateProducts = (arr) =>
  arr.map(({ popularity, ...item }) => ({
    popularity: popularity ?? Math.floor(Math.random() * 100) + 1,
    ...item,
  }));

console.log(updateProducts(products));

Incorporating an element into a nested array

Answer №1

Answer №2

Answer №3

Answer №4

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