I'm working to a script to reoder an array with javascript. When I've a duplicate value on the second column, I would like to order this duplicate value by index order and push it on new array.
The aim is to transform array like this :
myarr = [
[5, 7]
[2, 8]
[3, 7]
];
var valeurcroiss = myarr.sort(compareSecondColumn);
var valeurdecroiss = valeurcroiss.reverse();
valeurdecroiss.length = 3;
function compareSecondColumn(a, b) {
if (a[1] === b[1]) {
return 0;
}
else {
return (a[1] < b[1]) ? -1 : 1;
}
}
Result that I have:
[
0: (2) [5, 7]
1: (2) [3, 7]
2: (2) [2, 8]
];
Result I would like to have:
[
0: (2) [2, 8]
1: (2) [3, 7]
2: (2) [5, 7]
];
Thank you for your help
Replace this line
return (a[1] < b[1]) ? -1 : 1;
with:
return (a[1] < b[1]) ? 1 : -1;
If there's a duplicate in the second column it'll already be arranged correctly if the first column is already arranged properly. So check for duplicates in index 0 and sort them out by index 1 and sort the rest by index 0.
const pairs = [[5, 7], [2, 8], [3, 7], [2, 6]];
let output = pairs.sort((a, b) => a[0] === b[0] ? a[1] - b[1] : a[0] - b[0]);
console.log(output);