Showing maximum value of an object in an array when it as two max values

Question

I have an array from the api response and its objects.I need to find the value which has maximum total and I have display it I'm unable to solve it , when there are two max values of the total.Is there any solution?

myArray[
{time: "2018-12-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-13-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-14-02", total: 35, percentage: 25, averageTime: 25},
{time: "2018-16-02", total: 65, percentage: 60, averageTime: 20},
{time: "2018-17-02", total: 40, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 65, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 35, percentage: 23, averageTime: 20}
];

I tried reduce function like this:

var data =[];
data.reduce((max, p) => p.total > max ? p.total : max, data[0].total);

What do you mean by 'when there are two max values of the total'? — Cata John, Mar 14 '18 at 06:54
What do you want to display when there are two maximums? Both or either one or the earlier one or the later one? What if there are three, four? Or do you just need the max total value? — Aydin4ik, Mar 14 '18 at 06:56
I need to display the time of when two objects has same highest 'total' value. — Hema Nandagopal, Mar 14 '18 at 06:57
So in case multiple objects have the same 'maximum' value you need to return the time of all of them? — Cata John, Mar 14 '18 at 06:59

score 2 · Accepted Answer · edited Jun 20 '20 at 09:12

You can do something like this:

Idea:

Create a hashMap with total as keys and a variable to hold max value.
Check if the key exists and if not, initialize it to an array.
Push current object in this array.
Fetch the array with the key as max and you will get all the values with max total.

Now that you have entire object, you can iterate and display any necessary values.

var myArray = [{time: "2018-12-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-13-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-14-02", total: 35, percentage: 25, averageTime: 25},
{time: "2018-16-02", total: 65, percentage: 60, averageTime: 20},
{time: "2018-17-02", total: 40, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 65, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 35, percentage: 23, averageTime: 20}]

var max = 0;
var hashMap = myArray.reduce((acc, p) => {
  max = Math.max(max, p.total);
  acc[p.total] = acc[p.total] || [];
  acc[p.total].push(p);
  return acc;
}, {});

console.log(hashMap[max]);

With only time value

var myArray = [{time: "2018-12-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-13-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-14-02", total: 35, percentage: 25, averageTime: 25},
{time: "2018-16-02", total: 65, percentage: 60, averageTime: 20},
{time: "2018-17-02", total: 40, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 65, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 35, percentage: 23, averageTime: 20}]

var max = 0;
var hashMap = myArray.reduce((acc, p) => {
  max = Math.max(max, p.total);
  acc[p.total] = acc[p.total] || [];
  acc[p.total].push(p.time);
  return acc;
}, {});

console.log(hashMap[max]);

Instead of getting the full object,Can you help to get the 'time' alone? — Hema Nandagopal, Mar 14 '18 at 07:05
Kindly check the update. Though I prefer getting entire object. This way, its more flexible. — Rajesh, Mar 14 '18 at 07:10

score 1 · Answer 2 · answered Mar 14 '18 at 06:54

You can use Math.max along with spread and array.prototype.map:

var myArray = [
{time: "2018-12-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-13-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-14-02", total: 35, percentage: 25, averageTime: 25},
{time: "2018-16-02", total: 65, percentage: 60, averageTime: 20},
{time: "2018-17-02", total: 40, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 65, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 35, percentage: 23, averageTime: 20}
];

var max = Math.max(...myArray.map(e => e.total));

console.log(max);

score 0 · Answer 3 · answered Mar 14 '18 at 07:03

You can find the maximum 'total' value in the array and then find all the elements of the array with that maximum value.

var myArray = [
{time: "2018-12-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-13-02", total: 25, percentage: 20, averageTime: 20},
{time: "2018-14-02", total: 35, percentage: 25, averageTime: 25},
{time: "2018-16-02", total: 65, percentage: 60, averageTime: 20},
{time: "2018-17-02", total: 40, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 65, percentage: 20, averageTime: 20},
{time: "2018-18-02", total: 35, percentage: 23, averageTime: 20}
];

var max = Math.max(...myArray.map(e => e.total));
var time = myArray.filter(item => item.total == max);

console.log(time);

You are looping twice. You can achieve this in same loop. Feel free to refer to my answer. — Rajesh, Mar 14 '18 at 07:04

score 0 · Answer 4 · answered Mar 14 '18 at 07:06

0

One possible approach:

function getMaxValue(myArray) {
    var totals = myArray.map(x => x.total);
    var max = filter(x => x == Math.max(totals));
    return max.length == 1 ? max[0] : 'unable to solve it';
}

answered Mar 14 '18 at 07:06

guijob

4,413
3
20
39

Showing maximum value of an object in an array when it as two max values

4 Answers4

Idea:

With only time value