I'm trying to sort the objects in the array using selection sort algorithm in javascript

Question

Here's what I'm trying to output:

[ { name: 'harry', age: '21' },
  { name: 'john', age: '23' },
  { name: 'jack', age: '25' } ]

but I'm getting this:

[ { name: 'john', age: '23' },
  { name: 'harry', age: '21' },
  { name: 'jack', age: '25' } ]

Here's my code:

  var persons = [
  {
  "name": "john",
  "age": "23"
  },
  {
  "name": "harry",
  "age": "21"
  },
  {
  "name": "jack",
  "age": "25"
  }
];

function selectionSortObjects (arr){
  var length = arr.length;
  for(var i = 0; i < length; i++){
    var min = [i].age;
    for(var j = i+1; j < length; j++) {
      if(arr [j].age > arr[min]){
        min = [j].age;
      }
    }
    if (min != i.age) {
      var k = arr[i].age;
      arr[i].age = arr[min];
      arr[min] = k;
    }
  }
  return arr;
}

console.log(selectionSortObjects(persons));
// console.log(persons[0].age);

What am I doing wrong? Because I'm getting no errors, but I'm getting the wrong output. I'm trying to sort the result by age doing the selection sort algorithm.

Use Array.prototype.sort and pass in a comparator function which does e.g. return b.age - a.age; — Paul S.
– Paul S., Commented Oct 1, 2015 at 1:17

Web and Flow · Accepted Answer · 2015-10-01 01:41:57Z

4

You asked for selection sort method. This is not it but will give you the result you want based on the input provided.

persons.sort(function(a, b){return a.age-b.age});

Since persons is an array we can use the array sort and pass a custom function that compares the age within each object within the array

edited Oct 1, 2015 at 1:41

answered Oct 1, 2015 at 1:21

Web and Flow

1438 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Fernando Gomez Over a year ago

but isn't that using the sort method? I'm trying to do the selection merge algorithm.

Web and Flow Over a year ago

Did not get that from the question. You mention needing to sort an array of objects. I did infer from the examples that you wanted to sort by age but was I incorrect? If so, please explain your problem in more detail in the original question

Triet Doan · Accepted Answer · 2015-10-01 02:01:26Z

0

I modified your selectionSortObjects function to make it works as you expected. Here is the new version:

function selectionSortObjects (arr){
  var length = arr.length;
  for(var i = 0; i < length; i++){
      var min = {
          value: arr[i],
          index: i
      }
    for(var j = i+1; j < length; j++) {
      if(arr[j].age < min.value.age){
        min.value = arr[j];
          min.index = j;
      }
    }
    if (min.value != arr[i]) {
      var k = arr[i];
      arr[i] = min.value;
      arr[min.index] = k;
    }
  }
  return arr;
}

Take a look at full source code in JSFiddle.

answered Oct 1, 2015 at 2:01

Triet Doan

12.2k9 gold badges42 silver badges76 bronze badges

Collectives™ on Stack Overflow

I'm trying to sort the objects in the array using selection sort algorithm in javascript

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related