RE: [office-formula] serial number? Don't we mean serial date?

[Andreas J Guelzow <aguelzow@math.concordia.ab.ca>]

On Wed, 2010-01-27 at 12:36 -0800, Dennis E. Hamilton wrote:
Rob, I mainly agree that there is no "type," Serial Day, but there are
an
> incredible number of places where the current OpenFormula functions
produce
> and accept Number values that are interpreted as serial-day values as
part
> of the definition of those functions.
> 
Are there really? Aren't most simply conversions? Off the top of the
head I can't come up with one function that really depends on this
conversion!

THE USUAL ADDITIONAL THOUGHTS
> 
> Many OpenFormula functions depend implicitly on the global
origin-date/epoch
> value and the calendar mapping that goes with that origin date.  This
is
> true for anything involving a start-date and end-date parameter,
especially
> YEARFRAC and anything that has time-period basis adjustments that
depend on
> the actual calendar periods involved.  
> 
I don't see how this depends (indirectly or otherwise) on the global
origin-date/epoch value and the calendar mapping. 

Could you explain please

We can't define these functions
> without acknowledging the existence of a mapping known to the
implementation
> of the functions and talking about the dates those mappings correspond
to.
> The DATEDIF function is a particularly interesting case of this
> interdependence.
> 
The definition of datedif is: 
Returns the difference in years, months, or days of two date numbers.
[plus a table to handle left overs]

How does this depend on the number<->date mappping?

Andreas

> 

-- 
Andreas J. Guelzow
Concordia University College of Alberta