How can I sort an array of key : objects based on object values

Question

I have my data like this

I am trying to sort it like this

$initialArrayBTC.sort(function (a, b) {
    return b.q - a.q //Trying to sort is on the base of "q" in descending order
});

But this does not seem to work although I looked through many stackoverflow answers. Can anyone help me what might be the issue?

EDIT This is my all data inside the object

SAMPLE CODE

var $initialArrayBTC = [];
$initialArrayBTC['A'] = {
  q: "3598"
};
$initialArrayBTC['B'] = {
  q: "123"
};
$initialArrayBTC['C'] = {
  q: "9999"
};
console.log($initialArrayBTC);

$initialArrayBTC.sort(function(a, b) {
  return b.q - a.q //Trying to sort is on the base of "q" in descending order
});

console.log($initialArrayBTC);

Is the result of b.q - a.q always either 1, 0 or -1 ? That's what the function has to return. — Dennisvdh, Jul 24 '18 at 06:25
the sort function returns a sorted array as far as I remember. Try `$initialArrayBTC = $initialArrayBTC.sort(....` — Prasun Jajodia, Jul 24 '18 at 06:25
Is "q" a field containing a number or string? You should parse de value if you have a string and expecting to sort by the value number. — Brank Victoria, Jul 24 '18 at 06:28
no need to convert a stringified number. the minus operator casts both operands to number, if not already a number. — Nina Scholz, Jul 24 '18 at 06:34
http://jsfiddle.net/8na74sb1/ it's working here, and I don't see any reason why it wouldn't in your case. — Jeto, Jul 24 '18 at 06:37
try to debug inside of your sort function what you getting value after `b.q - a.q` — Narendra Jadhav, Jul 24 '18 at 06:38
@Jeto you dont have String as keys. This is not an indexed array. — Ali Zia, Jul 24 '18 at 06:38
@AliZia they do have strings as keys, "q" is like a string, you can try adding double quotes but that won't change anything. What do you mean? — Jeto, Jul 24 '18 at 06:41
@Jeto but my structure is different from your array. Please verify. — Ali Zia, Jul 24 '18 at 06:42
@AliZia can you please do a jsfiddle with your structure, please? I am with Jeto and I've seen it working. — Brank Victoria, Jul 24 '18 at 06:43
@AliZia It's not. It's an array of objects, mine just doesn't have the other keys (because they're meaningless in your case). But yeah, just post a sample (don't have to use jsfiddle, you can edit your OP too). — Jeto, Jul 24 '18 at 06:44
I am just seeing that the function inside the sort is not executing. — Brank Victoria, Jul 24 '18 at 06:51
Yes, something is wrong with the structure of your variable, I am seeing that your array has size 0, thats why is not executing. If you do: $initialArrayBTC.length you can see that is "0" — Brank Victoria, Jul 24 '18 at 06:54
you are trying to sort an object, not an array, even if you use an array with properties. the array sort works only for indexed (numbers as keys) properties. — Nina Scholz, Jul 24 '18 at 06:55
That is not an array `$initialArrayBTC['A']` like you are thinking. Arrays in Javascript are indexed, JS doesn't have associative arrays. — connexo, Jul 24 '18 at 06:55
You cannot key them. Also, your question does not have anything to do with jQuery. — connexo, Jul 24 '18 at 06:56
Possible duplicate of [Sorting JavaScript Object by property value](https://stackoverflow.com/questions/1069666/sorting-javascript-object-by-property-value) — Brank Victoria, Jul 24 '18 at 07:02

Nina Scholz · Accepted Answer · 2018-07-24T07:06:47.177

You could build a new object by creating the properties in the wanted order, but this may works only with not integer numbers (numbers as indices for array) as keys and maybe not in all browsers.

You could take an object and then the keys of it, sort them and use the sorted keys for a sorted output.

var $initialArrayBTC = {};

$initialArrayBTC['A'] = {q: "3598"};
$initialArrayBTC['B'] = {q: "123"};
$initialArrayBTC['C'] = {q: "9999"};

var keys = Object.keys($initialArrayBTC).sort(function (a, b) {
  return $initialArrayBTC[b].q - $initialArrayBTC[a].q;
});

keys.forEach(k => console.log($initialArrayBTC[k]));

score 1 · Answer 2 · answered Jul 24 '18 at 07:02

1

Looks like your initial instance is an object, as opposed to an array. You can grab its keys, sort the keys by values, then rebuild the object:

const $initialArrayBTC = {
  A: {q: '3598'}, 
  B: {q: '123'},
  C: {q: '9999'}
};

const result = Object.keys($initialArrayBTC)
  .sort((key1, key2) => $initialArrayBTC[key2].q - $initialArrayBTC[key1].q)
  .map(key => ({[key]: $initialArrayBTC[key]}));

console.log(result);

answered Jul 24 '18 at 07:02

Jeto

14,596
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Thankyou. I am now creating a new array without keys and sorting it with my existing function. – Ali Zia Jul 24 '18 at 07:12

How can I sort an array of key : objects based on object values

2 Answers2