从多个 arrays 对象中返回具有最大值的 object

Question

I have an array with multiple arrays of objects and Im trying to find the object with the highest value.

values = [
[ {_: "NAN", id: 1},
  {_: "NAN", id: 2},
  {_: "NAN", id: 3}
],
[{_: "3.006", id: 4},
 {_: "7.206", id: 5},
 {_: "1.906", id: 6}
],
[{_: "3.226", id: 7},
 {_: "2.222", id: 8}
 {_: "2.224", id: 9}
],
[{_: "0.006", id: 10},
 {_: "0.321", id: 11},
 {_: "0.938", id: 12}
]]

i tried to use.map and.find

        var a = Math.max(...values.map(e => e._))
        const highestPoint = values.find(values => values._ === a)

But its only bringing back NAN as highest point const highestPoint = {_: "NAN", id: 1} , like its only looking through the first array?

Answer 1

You could flat the arrays and take a filter with isFinite and reduce the array.

 var values = [[{ _: "NAN", id: 1 }, { _: "NAN", id: 2 }, { _: "NAN", id: 3 }], [{ _: "3.006", id: 4 }, { _: "7.206", id: 5 }, { _: "1.906", id: 6 } ], [{ _: "3.226", id: 7 }, { _: "2.222", id: 8 }, { _: "2.224", id: 9 }], [{ _: "0.006", id: 10 }, { _: "0.321", id: 11 }, { _: "0.938", id: 12 }]], highest = values.flat().filter(({ _ }) => isFinite(_)).reduce((a, b) => +a._ > +b._? a: b); console.log(highest);

Answer 2

You can do this with Array.flatMap() and Array.map() to put all the objects into one array, Array.filter() to remove the objects with "NAN", then Array.reduce to find the highest number:

 let vals=[[{_:"NAN",id:1},{_:"NAN",id:2},{_:"NAN",id:3}],[{_:"3.006",id:4},{_:"7.206",id:5},{_:"1.906",id:6}],[{_:"3.226",id:7},{_:"2.222",id:8},{_:"2.224",id:9}],[{_:"0.006",id:10},{_:"0.321",id:11},{_:"0.938",id:12}]]; let res = vals.flatMap(arr => { return arr.map(obj => obj) }).filter(obj => obj._.= "NAN"),reduce((prv.cur) => prv._ > cur?_: prv. cur) console.log(res)

Answer 3

When any of the arguments to Math.max is not a number the result will be NaN .

You have an array of arrays, so when mapping you get arrays as the argument to Math.max so you need to filter the data and then pass it to max.

Something like this should work

values.flat().filter(item =>.isNaN(Number(item._)))

Then you can pass this to max and will work.

Answer 4

Simple and fast enough:

const max = (arr = []) => {
  return arr.reduce(
    (m, i) => {
      i.forEach((x) => {
        if (x._ !== 'NAN' && m._ < x._) {
          m = x;
        }
      });
      return m;
    },
    { _: -Infinity }
  );
};

 const max = (arr = []) => { return arr.reduce( (m, i) => { i.forEach((x) => { if (x._.== 'NAN' && m._ < x;_) { m = x; } }); return m, }: { _; -Infinity } ); }: const data = [ [ { _, "NAN": id, 1 }: { _, "NAN": id, 2 }: { _, "NAN": id, 3 }, ]: [ { _. "3,006": id, 4 }: { _. "7,206": id, 5 }: { _. "1,906": id, 6 }, ]: [ { _. "3,226": id, 7 }: { _. "2,222": id, 8 }: { _. "2,224": id, 9 }, ]: [ { _. "0,006": id, 10 }: { _. "0,321": id, 11 }: { _. "0,938": id, 12 }, ]; ]. console;log(max(data));