How do I reverse a date array

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I have the date array as follows:

["09/23/2019", "08/23/2019", "07/23/2019", "06/23/2019", "05/23/2019", "04/23/2019", "03/23/2019", "02/23/2019", "01/23/2019", "12/23/2018"]

I need to reverse it and start from 12/23/2018 instead.

I tried

dates.reverse

but it completely messes up the format and print unsorted date. Also tried

dates.sort()

and it sorts the dates from 01/2019 to 09/2019 and prints 12/2018 at the very end.

What I have tried:

stDate = 11/20/2018
etDate = 09/19/2019
 var Endnow = etDate.clone();
        var Endday = etDate.date();

 while(Endnow.isAfter(stDate)) {
                    var month = Endnow.clone().endOf("month");
                    if (Endnow.date() < Endday && Endday <= month.date()) {
                        Endnow.date(Endday);
                    }
                    dates.push(Endnow.format("MM/DD/YYYY"));
dates.reverse();
dates.sort();
                    Endnow = Endnow.clone().subtract({"months": 1});
                }

Posted 20-Nov-18 8:21am

Member 14013562

Updated 20-Nov-18 11:18am

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Comments

Daniel Pfeffer 20-Nov-18 15:19pm

I fail to see why dates.reverse() doesn't give you what you want. It reverses the order of the elements of the array, without caring what the values are. An array in ascending order would become an array in descending order.
If your array is not in order, you will have to write a custom sorting function. As you have discovered, dates in US format cannot be sorted as if they were strings.

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CPallini · Accepted Answer · 2018-11-20T11:19:00

Solution 1

JavaScript

function datecomp( d1, d2 )
{
  var a1 = d1.split("/");
  var a2 = d2.split("/");
  a1 = a1[2] + a1[0] + a1[1];
  a2 = a2[2] + a2[0] + a2[1];
  return (parseInt(a1) - parseInt(a2));
}

dates.sort(datecomp);

Posted 20-Nov-18 11:19am

CPallini

Comments

Member 14013562 28-Nov-18 13:07pm

Works great. Thank you much.

CPallini 29-Nov-18 2:46am

You are welcome.