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"Bob Scott" <rlscott@xxxxxxxx> wonders:
>I agree completely with what you indicate but I would like to
>clarify that the 'plus or minus 32768 or greater' must take into
>account the price scale used in the Symbol Universe... I have never
>tried it but I suppose you could regain historical tick data by
>rescaling the symbol in the Symbol Universe and then pasting in tick
>data downloaded from the Omega Research ftp site.
The offsets are stored as sixteen-bit numbers so that's the limit
where tick values will "wrap" or perhaps be clamped to the plus or
minus rail. The interesting question is whether the scaling factor
has anything to do with the storage process, or is simply used when
the data is pulled out for use by charting. The scale factor IS
stored in the tick database, but I've never checked to see if that
stored value changes if you alter it in the Symbol Universe.
It'd be interesting to try your rescaling experiment, and see if
the scale factor stored in the new data overrode the one you had
set in your Symbol Universe, or what. Another experiment would
be to change your SU scaling, then change it back, and see if
you lose bits off the low end.
Fun stuff... :)
Jim
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