Re: ODFF1.2 interpretation of function WEEKNUM

On 18/09/17 16:20, Winfried Donkers wrote:
> Hi Eike,
>
>
> I'm working on tdf112320 and I think that ODFF1.2 may be ambiguous with
> respect to WEEKNUM
> (http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part2.html#WEEKNUM)
>
>
> My interpretation of the Semantics for Mode 1,2,11-17 was that
>
> 'every week starts on Sunday..Saturday, depending on the value of Mode.
> The week containing 1 January is week 1'.
>
> So, WEEKNUM(DATE(2014,12,29),1) returns 1, as it is a Monday, the week
> starts on Sunday 28 December and 1 January is on the Thursday. All weeks
> have 7 days.
>
>
> However, both Excel and Gnumeric use
>
> 'every week starts on Sunday..Saturday, depending on the value of Mode,
> _or_ on 1 January (with the week number 1)'.
>
> So, WEEKNUM(DATE(2014,12,29),1) returns 53, as it is a Monday, following
> week 52 and WEEKNUM(DATE(2015,1,1),1) returns 1. Week 53 has 4 days and
> week 1 has 3 days.

I really should read your link to the spec before shooting from the
hip... :-(

But I googled for Excel's definition of weeknum, and found

https://support.office.com/en-gb/article/WEEKNUM-function-e5c43a03-b4ab-426c-b411-b18c13c75340

This reads to me exactly like the ODF spec, so it seems that Excel is
not abiding by the Excel spec if it returns 29-dec as week 53 ...

To quote the Excel spec, "System 1    The week containing January 1 is
the first week of the year, and is numbered week 1." That says to me -
as a native English speaker, that it is a complete week INCLUDING ANY
DAYS BEFORE JAN 1.

So yes. It looks like Excel does not do what it says it does. Quelle
Surprise.

Cheers,
Wol