Numeric sort on an array with javascript

Question

I have this array :

[ [ 1, 'a' ], [ 2, 'b' ], [ 1, 'd' ], [ 9, 'e' ], [ 1, 'f' ], [ 11, 'g' ], [ 9, 'h' ], [ 3, 'i' ] ]

and I would like to have :

[ [ 11, 'g' ], [ 9, 'e' ], [ 9, 'h' ], [ 3, 'i' ], [ 2, 'b' ], [ 1, 'a' ], [ 1, 'd' ], [ 1, 'f' ] ]

How can I do that with javascript please ?

I tried sort() , I also tried with sort(compare) with :

function compare(x, y) {
  return x - y;
}

Answer 1

You can use .sort() with Array Destructuring like this:

function compare([a], [b]) {
  return b - a;
}

Demo:

 let a = [ [ 1, 'a' ], [ 2, 'b' ], [ 1, 'd' ], [ 9, 'e' ], [ 1, 'f' ], [ 11, 'g' ], [ 9, 'h' ], [ 3, 'i' ] ]; a.sort(compare); function compare([a], [b]) { return b - a; } console.log(a); 

 .as-console-wrapper { max-height: 100% !important; top: 0; } 

---

In case first elements match, you can sort based on 2nd element as well:

function compare([a, c], [b, d]) {
  return (b - a) || c.localeCompare(d)
}

Demo:

 let a = [ [ 2, 'b' ], [ 1, 'd' ], [ 9, 'e' ], [ 1, 'f' ], [ 11, 'g' ], [ 9, 'h' ], [ 3, 'i' ], [ 1, 'a' ] ]; a.sort(compare); function compare([a, c], [b, d]) { return (b - a) || c.localeCompare(d); } console.log(a); 

 .as-console-wrapper { max-height: 100% !important; top: 0 } 

Answer 2

You need to compare the first element in the nested array since you want to sort based on that number.

function compare(x, y) {
  return y[0] - x[0];
}

 var data = [ [1, 'a'], [2, 'b'], [1, 'd'], [9, 'e'], [1, 'f'], [11, 'g'], [9, 'h'], [3, 'i'] ]; function compare(x, y) { return y[0] - x[0]; } data.sort(compare); console.log(data); 

---

In case you want to sort based on second element(secondary sorting in case the first element is same) then use String#localeCompare method for comparing.

function compare(x, y) {
  return y[0] - x[0] || x[1].localeCompare(y[0]);
}

 var data = [ [2, 'b'], [1, 'd'], [9, 'e'], [1, 'f'], [1, 'a'], [11, 'g'], [9, 'h'], [3, 'i'] ]; function compare(x, y) { return (y[0] - x[0]) || x[1].localeCompare(y[1]); } data.sort(compare); console.log(data); 

Answer 3

Compare the elements based on their first element, which is the number.

 var a = [ [ 1, 'a' ], [ 2, 'b' ], [ 1, 'd' ], [ 9, 'e' ], [ 1, 'f' ], [ 11, 'g' ], [ 9, 'h' ], [ 3, 'i' ] ]; a = a.sort((a,b) => { return b[0] - a[0] }); console.log(a) 

Answer 4

Use sort to compare first element and if first element is same then compare the second element .

arr.sort( (a,b) => (b[0] - a[0]) || (b[1] - a[1]) )

Demo

 var arr = [ [ 1, 'a' ], [ 2, 'b' ], [ 1, 'd' ], [ 9, 'e' ], [ 1, 'f' ], [ 11, 'g' ], [ 9, 'h' ], [ 3, 'i' ] ]; arr.sort( (a,b) => (b[0] - a[0]) || (b[1] - a[1]) ); console.log(arr);