How do we get the most different value from object and print out the key of the value

Question

I have an object like this

{ '1': 2, 
  '2': 2, 
  '4': 2, 
  '5': 2, 
  '-2': 2, 
  '-1': 1 
}

Yeah we know, that the most different value from it is '1'

So the function will print out the keys from the object '-1'

Which function to find the key?

It takes about a few hours and I still not found it, because the object is a string

Any help would be appreciated, thanks

what do you mean by ```most different```? do you mean exist in least number as in there are 5 twos and 1 one(s) in your example? — Kristian, Feb 26 '21 at 07:49
I mean, the object -1 has the value 1, and it's the most different right?. What the question is, how to get the -1 — theDreamer911, Feb 26 '21 at 07:52
thanks @Miro , it help for clearing the question, can you also help with the solution too? — theDreamer911, Feb 26 '21 at 07:53
I think this should answer your question: https://stackoverflow.com/questions/46917849/how-to-get-least-frequent-item-of-array-javascript — Jens van Groeningen, Feb 26 '21 at 07:54
your question needs more clarification as what happens when you have two or more ones or is it always just one that's different than the rest? What's the bigger purpose? — Miro, Feb 26 '21 at 07:54
@JensvanGroeningen thanks for giving an advice, did you know how to get it, when it using object not array — theDreamer911, Feb 26 '21 at 08:03

Miro · Accepted Answer · 2021-02-26T09:31:40.040

1

You may need to iterate twice over the object to first find the least frequent and then get the key of the resulting value. There may be an easier way that I don't know about.

let obj = { '1': 2, 
  '2': 2, 
  '4': 2, 
  '5': 2, 
  '-2': 2, 
  '-1': 1 
}


function leastFrequentObjKey(obj) {
    var dict = {};
    Object.values(obj).forEach(val => {
        if (!dict[val]) dict[val] = 0;
        dict[val]++;
    });
    
    var value = Math.min.apply(null, Object.values(dict));
    return Object.keys(obj).find(key => obj[key] == value );
}



console.log( leastFrequentObjKey(obj) );

edited Feb 26 '21 at 09:31

answered Feb 26 '21 at 08:14

Miro

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you are really kind Miro, oh I see, that we can iterate two times inside object. Thanks – theDreamer911 Feb 26 '21 at 08:16
@theDreamer911 check the edit - single function only – Miro Feb 26 '21 at 09:32

score 0 · Answer 2 · answered Feb 26 '21 at 08:32

0

Use reduce method on Object.keys should simplify.

let obj = { 1: 2, 2: 2, 4: 2, 5: 2, "-2": 2, "-1": 1 };

const res = Object.keys(obj).reduce((min, key) =>
  obj[min] > obj[key] ? key : min
);

console.log(res)

answered Feb 26 '21 at 08:32

Siva K V

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this finds the smallest value. OP wants least frequent – Miro Feb 26 '21 at 08:41
@Miro, It is getting the least frequent (least value)'s corresponding key, which is '-1' in this case right? – Siva K V Feb 26 '21 at 09:58
It just happens to work in this case. However if `1:-5` and `2:-5` it will return 1. He wants the least frequent -- not just the lowest. – Miro Feb 26 '21 at 10:02

How do we get the most different value from object and print out the key of the value

2 Answers2