Re: [office] Excel 2007 != Ecma spec YEARFRAC. Not even slightly. What should we do?

["Warren Turkal" <turkal@google.com>]

I don't think that we should standardize the excel algorithms What if
we just have a registry of compatibility bases that is maintained
separately from the ODF spec? We could just reserve 5000 basis numbers
that represent a compatibility bases and a 200 or so for a private
area that will never be allocated in the registry for experimentation.

wt

On Thu, Apr 17, 2008 at 9:55 AM, David A. Wheeler <dwheeler@dwheeler.com> wrote:
> Ideally there'd be worldwide agreement.  But we need to decide what can be done if that will NOT happen soon.
>
>
>  >Maybe the solution is to have more than 5 bases?  We let 0-4 be the
>  >"Excel-compatible" options that match, as much as we can ascertain, what
>  >Excel 2007 does.  Then we have additional options 5, 6, 7, etc., that
>  >match current external financial authorities exactly.
>
>  I'd rather there be a bigger number gap for the different options.
>  We could define basis=128, 129, 130, and so on, and define both
>  Excel-2007-compatible algorithms and official algorithms.
>  If you use basis=128 in OpenDocument, then you'd be guaranteed to get
>  a particular algorithm.
>
>  That still doesn't resolve how to deal with basis=0 through 4.
>  If we can separate the algorithms from the basis mappings for 0..4,
>  we might be able to get the best of both worlds.  I.E., you could have a
>  recalculation setting that determined how basis 0..4 mapped.
>  Here's one approach: add a parameter called "basis_offset" to the sheet;
>  it's a value added to the basis value before YEARFRAC
>  and friends are called if the basis value < 128.
>  That would enable us to support many algorithm mappings, should
>  that prove to be necessary.
>  That's not ideal, but it's _an_ approach.  An advantage of this
>  approach is that we can handle legacy documents, which depended on
>  the Excel algorithms, as well as support standard basis values.
>  Other solutions welcome.
>
>  --- David A. Wheeler
>
>
>
>  ---------------------------------------------------------------------
>  To unsubscribe from this mail list, you must leave the OASIS TC that
>  generates this mail.  You may a link to this group and all your TCs in OASIS
>  at:
>  https://www.oasis-open.org/apps/org/workgroup/portal/my_workgroups.php
>
>