PSN-L Email List Message

Subject: Re: New PSN event file format.
From: The Lahrs johnjan@........
Date: Sun, 02 Jul 2000 18:52:15 -0600

At 04:18 PM 7/2/00 , you wrote:
>I made a few changes to the format (see
> based on the comments from Edward.
>All floats have been changed to doubles and I changed some bytes and shorts
>to longs. The variable length section can now have data fields larger then
>255 bytes.
>  Also, it would be useful to include a clock
> >correction in seconds as a double (type/length) that could be added to the
> >nominal time that the samples were originally time-stamped with when
> >Particularly in the case of "unlocked" data, that estimate of true time
>might be
> >fuzzy and controversial.
>It seems to me that the start time should already include this information.
>Basically the start time of the first sample is based on the best
>information the data logger has at the time it saves the data to disk.
Hi Larry,

I think the problem is that if the time originally recorded for the first 
sample is
not correct, then it's better to use a correction field than to simply 
change the
number that was originally stored with the file.  In that way, one always
knows what the original time stamp was and the correction tells how far
the clock was off.  If you later figure out a better clock correction, then a
new correction can be used and you never loose track of what you're doing,
or have done.

John C. Lahr
1925 Foothills Road
Golden, CO 80402
(303) 215-9913

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Larry Cochrane <cochrane@..............>