CODEWITHSUNDEEP
javascript
AC_Valhalla
AC_Valhalla

Reputation: 161

How to sort an array of objects using another array for reference?

i want to sort an array of objects having id each object using another array that only has the ids, for example:

object = [
 {id: 2, name: carlos},
 {id: 1, name: maria},
 {id: 4, name: juan},
 {id: 3, name: pepe},    //this is the array that i want to be sorted or create a copy to return it
]


    [1,2,3,4,5] //this is the array that i will use as reference to sort the first one

the final result should be:

object = [
 {id: 1, name: maria},
 {id: 2, name: carlos},
 {id: 3, name: pepe},
 {id: 4, name: juam},    //this is the array that i want to be sorted or create a copy to return it
]

im using two maps, but im always getting and array with undefined:

array_to_be_sorted.map((objects) => {
  array_reference.map((id) => {
     if (objects.id === id) {
        return {...objects}
     }
  }    
}

im using map cause think is the best way for bigs array, because im building a music player, so dont know how many tracks the does the user has

Upvotes: 0

Views: 404

Answers (3)

Hassan Imam
Hassan Imam

Reputation: 22534

You can take advantage of Schwartzian transform and sort data based on another array.

const data = [ { id: 2, name: 'carlos' }, { id: 1, name: 'maria' }, { id: 4, name: 'juan' }, { id: 3, name: 'pepe' }, ],
      order = [4, 2, 3, 1, 5],
      result = data.map(o => {
                const index = order.indexOf(o.id);
                return [index, o];
              })
              .sort((a, b) => a[0] - b[0])
              .map(([, o]) => o);
console.log(result);

Upvotes: 0

terrymorse
terrymorse

Reputation: 7086

Why not just use Array.prototpye.sort()? It's easy and fast.

const pre = document.querySelector('pre');

let object = [
  {id: 2, name: 'carlos'},
  {id: 1, name: 'maria'},
  {id: 4, name: 'juan'},
  {id: 3, name: 'pepe'}
];

const criteria = [1,2,3,4,5];

pre.innerText = 'object:' + JSON.stringify(object, null, 2) + '\n\n';

object.sort((a, b) => {
  return criteria[a.id] - criteria[b.id];
});

pre.innerText += 'sorted object:' + JSON.stringify(object, null, 2);
Sort an array using criteria from a second array:

<pre></pre>

Upvotes: 0

phi-rakib
phi-rakib

Reputation: 3302

You could use Array.prototype.sort() method to get the result.

const data = [
  { id: 2, name: 'carlos' },
  { id: 1, name: 'maria' },
  { id: 4, name: 'juan' },
  { id: 3, name: 'pepe' },
];

const order = [1, 2, 3, 4, 5];
data.sort((x, y) => order.indexOf(x.id) - order.indexOf(y.id));
console.log(data);

Another solution using Map Object which is faster than the first one.

const data = [
  { id: 2, name: 'carlos' },
  { id: 1, name: 'maria' },
  { id: 4, name: 'juan' },
  { id: 3, name: 'pepe' },
];

const order = [1, 2, 3, 4, 5];
const map = new Map();
order.forEach((x, i) => map.set(x, i));
data.sort((x, y) => map.get(x.id) - map.get(y.id));
console.log(data);

Upvotes: 2

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