JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>

JavaScript

$(function(){
var result = {
  status: 200,
  error: false,
  msg: "Successful response",
  data: {
    "horodate": ["2016-10-13 00:00:00", "2016-10-13 00:30:00", "x", "y", "z"],
    "value": [2609.479, 2390.026, 2320.394, 2276.602, 2247.151]
  }
}

var highest = 0;
var lowest = Number.MAX_VALUE;
var lowIndex = 0;
var highndex = 0;
var obj = {};

$(result.data.value).each(function(i,v){

 if (v > highest){
 highest = v;
 highndex = i
 } 
 
 if (v < lowest){
 lowest = v;
 lowIndex = i
 } 

if((i+1) == result.data.value.length){
   obj.highest = highest;
   obj.lowest = lowest;
   obj.dateHigh = result.data.horodate[highndex]
   obj.dateLow = result.data.horodate[lowIndex]
}


})
console.log(obj)
})