How to set start day of the week when formatting for week numbers

[jimmykane]

I tend to format for weeks aggragate data.

How can I set the starting weekday when formatting with ww YYY for example date objects (DateAxis)

[martynasma]

There's no way to do that, I'm afraid.

The common notion is that the week of the first Wednesday in the year is the first week of that year.

[jimmykane]

I don't argue about that, but to take into consideration if the users week starts on Monday or Sunday. People in US have their weeks starting in Sundays. Do you understand what I ask ?

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On Thu, 9 Jul 2020, 09:39 Martynas Majeris, ***@***.***> wrote: There's no way to do that, I'm afraid. The common notion is that the week of the first Wednesday in the year is the first week of that year. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#2682 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAJVX44FBA7HV4P5KSCKMW3R2VXZPANCNFSM4OU27OZA> .

[martynasma]

I do. Thought week of year is not being counted based on it's beginning, but rather one fixed day - Thursday (I'm sorry I was wrong in my first reply about it being Wed).

It's actually an ISO standard:
https://en.wikipedia.org/wiki/ISO_week_date#First_week

[jimmykane]

@martynasma the first week is determined by the Thursday.

However it lasts till Sun OR Monday. Then from that the week number is determined

This is what I am asking https://en.wikipedia.org/wiki/ISO_week_date#Other_week_numbering_systems

I am very familiar with the ISO's sorry if I was not clear.

[martynasma]

Gotcha. We will consider this. But can't promise anything right now :/

In the interim, I think the immediate solution would be to use adapters to calculate your own week number on axis labels.

[jimmykane]

We will consider this.

Take your time no rush. I was only asking if there was a way and looks like you provided one.

Thanks so much for your time

[rejochandran]

Hi @jimmykane

Have the same issue. Can you explain how you implemented a workaround?

I understand there are 2 things here

1. Logic for grouping into weeks (Sunday to Saturday)
2. Applying aggregation on top of it

I have an adapter set to compute custom aggregation but I am not able to define a custom grouping

[rejochandran]

Gotcha!
Was able to fix this by specifying the firstDayOfWeek property of dateFormatter in the dateAxis

dateAxis.dateFormatter.firstDayOfWeek = 0;  
// 0 - Sunday as the first day of the week

Ref: https://www.amcharts.com/docs/v4/reference/dateformatter/#firstDayOfWeek_property

Thank you!