Sort a 2D JavaScript array based on three columns which contain undefined values

Question

I'm trying to get three columns sorted in an array in Google Apps Script. I realize there are lots of explanations, but I'm not getting it. I was hoping someone could troubleshoot the code snipper below.

Desired functionality: sort an array using 'columns' 8,9,10 (text and nulls), in order.

Issue: nulls don't seem to get sorted properly.

Code snippet:

shdv.sort(function(a,b){
  var so = -1
a[10]>b[10] ? so=1 : null; // section
a[10] == b[10] && (a[9]>b[9] || a[9] == '') ? so=1 : null;
a[10] == b[10] && a[9]==b[9] && a[8]>a[9] ? so=1 : null;
null;
})

Example result

[Not Tracking, Site, 2.85208117E8]
[Not Tracking, , 2.83812926E8]
[Not Tracking, , 2.83991529E8]
[Not Tracking, Site, 2.83812602E8]

Desired result

[Not Tracking, Site, 2.85208117E8]
[Not Tracking, Site, 2.83812602E8]
[Not Tracking, , 2.83812926E8]
[Not Tracking, , 2.83991529E8]

Provide minimal reproducible example. Your sort function has typos and doesn't return anything. Also provide sample values for shdv — TheMaster
– TheMaster, Commented Jan 4, 2021 at 18:44
Can't you use range.sort([{column:8,ascending:true},{column:9,ascending:true},{column:10,ascending:true}]) Example here — Cooper
– Cooper, Commented Jan 4, 2021 at 18:58
@Cooper - thanks but this is for array only / no spreadsheet calls to fix this. — Jason Torpy
– Jason Torpy, Commented Jan 4, 2021 at 19:03

Marios · Accepted Answer · 2021-01-04 19:26:32Z

2

Explanation:

You are trying to sort based on undefined values in the array.
You can directly compare the elements like that: a[1]==undefined, b[1]==undefined;

Code snippet:

  const shdv = [
    ["Not Tracking", "Site", 2.85208117E8],
    ["Not Tracking", , 2.83812926E8],
    ["Not Tracking", , 2.83991529E8],
    ["Not Tracking", "Site", 2.83812602E8]
    ];
  
  shdv.sort( (a,b) => 
            // if same sort equally
            a[1]==b[1]?0:
            //if nulls put them in the bottom
            a[1]==undefined?1: 
            b[1]==undefined?-1:
            //sort based on 1st and 3rd element
            a[0].charCodeAt(0)-b[0].charCodeAt(0) || a[2]<b[2]  );
  console.log(shdv);

The console.log(shdv) in GAS returns the expected result:

References:

Array.prototype.sort()

answered Jan 4, 2021 at 19:26

Marios

27.5k9 gold badges40 silver badges59 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Jason Torpy Over a year ago

is there any potential issue with just doing a[1]==undefined?1: instead of ?1:null; the full argument and line close seems necessary. does documentation say all that is optional?

Marios Over a year ago

Not sure what you mean, but you can try it out if it works for you that way. However, I do prefer structured (complete) code so it is easy to be explained, maintained, understood. If less code works for you, then feel free to do it. But I don't think you will get more performance doing so in this scenario. @JasonTorpy Feel free to accept the answer if it solved your issue.

Jason Torpy · Accepted Answer · 2021-01-04 19:02:47Z

0

fix is to add at the end

return so;

so the sort actually sees the result. But I'm interested in any suggestions about how to do this better (array only / no spreadsheet calls)

answered Jan 4, 2021 at 19:02

Jason Torpy

1441 silver badge14 bronze badges

Collectives™ on Stack Overflow

Sort a 2D JavaScript array based on three columns which contain undefined values

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related