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Re: Decimal Presence Map Utilization
Joshua Go <>
28 Aug 2007 12:03PM ET I don't want to imply anything but from your previous reply...
<decimal name="price"><copy/></decimal>
will be encoded using the twin method, correct? And stored in one dictionary entry?
josh
> Atomic in the sense that it only relates to a single entry in the
> dictionary.
>
> The "single field" method is, as you say, not part of FAST 1.1.
>
> /David
>
> > "atomic value" ... are you implying it uses the single field method?
> > or the twin field method?
> >
> > <decimal name="price"><copy/></decimal>
> >
> > I've encountered a decimal field before with the above declaration,
> > but encoded using the twin method. Which I thought was the proper
> > implementation because I was told that the single field method was
> > depracated.
> >
> > josh
> >
> > > It occupies one or two slots depending on the value of the exponent
> > > as we've just discussed.
> > >
> > > They are not the same because in this case you treat the decimal as
> > > two individual integer fields with individual operator. In the prior
> > > case you treat the decimal as an atomic value. Those two cases are
> > > treated separately in the specification.
> > >
> > > From a practical point of view, comparing these two particular
> > > cases, I'd always use the prior one. More typical cases where
> > > individual operators are motivated use copy or constant and delta in
> > > combination.
> > >
> > > /David
> > >
> > > > Does that adhere to the latest spec?
> > > >
> > > >
> > > > How about this declaration? Does this also occupy one slot? It's
> > > > virtually the same as the prior declaration.
> > > >
> > > > <decimal name="price"> <exponent><copy/></exponent>
> > > > <mantissa><copy/></mantissa> </decimal>
> > > >
> > > >
> > > > Josh
> > > >
> > > > > Yes, it is valid and it will occupy exactly one PMAP slot.
> > > > >
> > > > > /David
> > > > >
> > > > > > <decimal name="price"> <copy/> </decimal>
> > > > > >
> > > > > > 1) Is this a valid declaration? 2) Will this occupy 1 PMAP
> > > > > > slot or 2 PMAP slots (exponent and mantissa)?
Re: Decimal Presence Map Utilization
Joshua Go 28 Aug 2007 12:03PM ET
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