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Re: 19990709: duplicate products in the noaaport idd

Bill,

That's some interesting results. I'll run some tests here.  The reason, I
asked about the sequence number because it's included in the checksum.
That needs to be change.  The arrival time is also important because there
has been times that the NWS resent the last 4 hours of data again over
NOAAport. I'll let you know what I find out. Currently, I'm preparing for
the LDM workshop presentation, so my time is limited now.

Robb...




On Fri, 9 Jul 1999, William Noon wrote:

> Robb -- The following are some links to the data I gathered last month.
> I basically looked at just the products (skipped sequence number and I don't
> have arrival time) by checksumming the product and sorting by product
> header:chksum pair.  I compared the data delivered from the alden satellite
> dd+ service to the idd feed.  I have the idd feed for April, May and the 
> first few days of June but only May for the dd+ feed.
> 
> http://nrcc2.cit.cornell.edu/~noon/ddp_dup.9905  # May dd+ feed
> http://nrcc2.cit.cornell.edu/~noon/idd_dup.9904  # April idd feed
> http://nrcc2.cit.cornell.edu/~noon/idd_dup.9905  # May idd feed
> http://nrcc2.cit.cornell.edu/~noon/idd_dup.9906  # June idd feed
> 
> Here is a file with more details,  It list the number of products, 
> number of duplicate products, and the headers of the products with
> more than 4 duplicates followed by the crc and dup count.
> This is only for June 8, 1999.
> 
> http://nrcc2.cit.cornell.edu/~noon/chk_ldm.990608
> 
> This was just exploratory and I didn't have time to delve into it more.
> 
> I can send you the python script that got the data if you want.
> 
> Thanks -- Bill Noon
> 
> 

===============================================================================
Robb Kambic                                Unidata Program Center
Software Engineer III                      Univ. Corp for Atmospheric Research
address@hidden             WWW: http://www.unidata.ucar.edu/
===============================================================================