find maximum number in array of objects?

Question

how I can find the bigger and smaller number in the most efficient way in javascript (or the most easiest way)

something like this:

function findMaxFromArray() {
  // logic
  return { x: ..., y: ... }
}

I tried Math.max(array.x) and is not working

here the array:

 let array = [{ "x": 0, "y": 0 }, { "x": 3.6417243968365076, "y": 10 }, { "x": 9.34437089784549, "y": 20 }, { "x": 0.7464057532722523, "y": 30 }, { "x": 10.254345841653576, "y": 40 }, { "x": 40.665266471734526, "y": 50 }, { "x": 13.605184580988041, "y": 60 }, { "x": 56.1970151503722, "y": 70 }, { "x": 46.30684270171864, "y": 80 }, { "x": 86.97417514998948, "y": 90 }, { "x": 19.086639005143002, "y": 100 }, { "x": 74.53073691009028, "y": 110 }, { "x": 80.51273650018987, "y": 120 }, { "x": 125.67651066602721, "y": 130 }, { "x": 94.92603682139705, "y": 140 }, { "x": 81.41258620429245, "y": 150 }, { "x": 128.79236053348222, "y": 160 }, { "x": 101.73294154449238, "y": 170 }, { "x": 176.92343490767377, "y": 180 }, { "x": 148.01122343809243, "y": 190 }, { "x": 13.666705559256798, "y": 200 }, { "x": 190.95447678085023, "y": 210 }, { "x": 186.02329838354444, "y": 220 }, { "x": 207.04643642736238, "y": 230 }, { "x": 75.3481702154557, "y": 240 }, { "x": 49.14228670472814, "y": 250 }, { "x": 203.65260758421869, "y": 260 }, { "x": 69.53501551989147, "y": 270 }, { "x": 269.52487694376975, "y": 280 }, { "x": 184.31351948105274, "y": 290 }, { "x": 19.72787138830958, "y": 300 } ]

result output:

basically, we give an array of objects with x , y as a parameter to a function.

and the function should return the maximum x and maximum y

(for now, I don't need to calculate the minimum since is always 0, but it will help as well as a solution in that topic too)

 // output sample return { x: 269.52487694376975, y: 300 } // or like this if it return also minimum return { max: { x: 269.52487694376975, y: 300 }, min: { x: 0 y: 0 } }

I have tried before, but with for loops, and isn't giving me any result at all. and a lot of code. (if possible a simple way)

thanks

Answer 1

Use Array.prototype.map and Math.max

 let array = [{ "x": 0, "y": 0 }, { "x": 3.6417243968365076, "y": 10 }, { "x": 9.34437089784549, "y": 20 }, { "x": 0.7464057532722523, "y": 30 }, { "x": 10.254345841653576, "y": 40 }, { "x": 40.665266471734526, "y": 50 }, { "x": 13.605184580988041, "y": 60 }, { "x": 56.1970151503722, "y": 70 }, { "x": 46.30684270171864, "y": 80 }, { "x": 86.97417514998948, "y": 90 }, { "x": 19.086639005143002, "y": 100 }, { "x": 74.53073691009028, "y": 110 }, { "x": 80.51273650018987, "y": 120 }, { "x": 125.67651066602721, "y": 130 }, { "x": 94.92603682139705, "y": 140 }, { "x": 81.41258620429245, "y": 150 }, { "x": 128.79236053348222, "y": 160 }, { "x": 101.73294154449238, "y": 170 }, { "x": 176.92343490767377, "y": 180 }, { "x": 148.01122343809243, "y": 190 }, { "x": 13.666705559256798, "y": 200 }, { "x": 190.95447678085023, "y": 210 }, { "x": 186.02329838354444, "y": 220 }, { "x": 207.04643642736238, "y": 230 }, { "x": 75.3481702154557, "y": 240 }, { "x": 49.14228670472814, "y": 250 }, { "x": 203.65260758421869, "y": 260 }, { "x": 69.53501551989147, "y": 270 }, { "x": 269.52487694376975, "y": 280 }, { "x": 184.31351948105274, "y": 290 }, { "x": 19.72787138830958, "y": 300 } ] const max = { x: Math.max(...array.map(e => ex)), y: Math.max(...array.map(e => ey)), } console.log(max)

Answer 2

 let array = [{ "x": 0, "y": 0 }, { "x": 3.6417243968365076, "y": 10 }, { "x": 9.34437089784549, "y": 20 }, { "x": 0.7464057532722523, "y": 30 }, { "x": 10.254345841653576, "y": 40 }, { "x": 40.665266471734526, "y": 50 }, { "x": 13.605184580988041, "y": 60 }, { "x": 56.1970151503722, "y": 70 }, { "x": 46.30684270171864, "y": 80 }, { "x": 86.97417514998948, "y": 90 }, { "x": 19.086639005143002, "y": 100 }, { "x": 74.53073691009028, "y": 110 }, { "x": 80.51273650018987, "y": 120 }, { "x": 125.67651066602721, "y": 130 }, { "x": 94.92603682139705, "y": 140 }, { "x": 81.41258620429245, "y": 150 }, { "x": 128.79236053348222, "y": 160 }, { "x": 101.73294154449238, "y": 170 }, { "x": 176.92343490767377, "y": 180 }, { "x": 148.01122343809243, "y": 190 }, { "x": 13.666705559256798, "y": 200 }, { "x": 190.95447678085023, "y": 210 }, { "x": 186.02329838354444, "y": 220 }, { "x": 207.04643642736238, "y": 230 }, { "x": 75.3481702154557, "y": 240 }, { "x": 49.14228670472814, "y": 250 }, { "x": 203.65260758421869, "y": 260 }, { "x": 69.53501551989147, "y": 270 }, { "x": 269.52487694376975, "y": 280 }, { "x": 184.31351948105274, "y": 290 }, { "x": 19.72787138830958, "y": 300 } ] console.log(Math.max(...array.map(elem => elem.x))) console.log(Math.max(...array.map(elem => elem.y))) console.log({ x:Math.max(...array.map(elem => elem.x)), y:Math.max(...array.map(elem => elem.y)) })

Answer 3

This function returns max number and min from array

function sortThem(numbers) {

  let minNum = numbers[0]
  let maxNum = numbers[0]

  for (let i = 0; i < numbers.length; i++) {
    if (minNum > numbers[i]) {
      minNum = numbers[i]
    } else if (maxNum < numbers[i]) {
      maxNum = numbers[i]
    }
  }

  const minMax = [minNum, maxNum]
  return minMax

}

Then use it like this

const results = sortThem([2, 9, 10, 17, 45])

console.log(results)

Answer 4

You can use Array.prototype.reduce() and calculate everything in one pass/iteration.

const array = [
  {
    x: 0,
    y: 0,
  },
  {
    x: 3.6417243968365076,
    y: 10,
  },
  {
    x: 9.34437089784549,
    y: 20,
  },
];

const findMaxAndMin = data => {
  return data.reduce(
    (acc, cur) => {
      return {
        max: {
          x: Math.max(cur.x, acc.max.x),
          y: Math.max(cur.y, acc.max.y),
        },
        min: {
          x: Math.min(cur.x, acc.min.x),
          y: Math.min(cur.y, acc.min.y),
        },
      };
    },
    { max: { x: null, y: null }, min: { x: null, y: null } }
  );
};

console.log(findMaxAndMin(array));

Answer 5

Here is an answer using Array.reduce.

// reduce loops on the array items and apply a callback function
const max = array.reduce(
  /**
   * callback function that is called for each element of the array from index 0 to index array.length-1
   * @param currentMax an object {x: number, y: number} containing the current maximum of x and y. It is initialized to the second argument of reduce
   * @param currentItem the current element of the loop
   * @returns the value of currentMax that will be used for the next step of the loop
   */
  (currentMax, currentItem) => {
    return {x: Math.max(currentMax.x, currentItem.x), y: Math.max(currentMax.y, currentItem.y)};
  }, array[0] /* initial maximum set to the first element of the array */);
console.log(max);

Answer 6

Hey you can use the underlying snippet to get your desired result:

var NewReturnObject = {
        min: {
            x: Math.min(...array.map(o => o.x)),
            y: Math.min(...array.map(o => o.y))
        },
        max: {
            x: Math.max(...array.map(o => o.x)),
            y: Math.max(...array.map(o => o.y))
        }
    }

    console.log(NewReturnObject);

For further references you can refer to underlying links as well: Obtain smallest value from array in Javascript and Finding the max value of an attribute in an array of objects