Re: 20010427: GEMPAK 5.6.C.1 Available

Greg,

The key issues about how long it takes to create a masaic are:
1) The number of gridded data points (I currently use 360,000 
   for both CONUS and regional)
2) The number of radar sites in the station table.

It takes about 10 minutes to run through the projection of all 153 radars
into the 360,000 point grid domain the first pass. Then, it takes
about 1 minute from then on for all the products thereafter since I save
the bounds for each radar in an array. You can also speed up a regional
mosaic be knowing ahead of time what nexrad stations will be in the domain
and using a smaller station table with just those IDs. You can create
this information from the output of the program since it will tell you
what radars are being used. I don't do this for my regional mosaic though since
I want it to be a floater- moving with the interesting weather. However,
sites that always want a region around them can take advantage of this.
I created the RADFRQ parameter so that the user can set up the 
wait time between each iteration of the program, so that
the program doesn't have to exit and lose the projection information
that it worked so hard to create.

Since it only takes a minute to produce the grid, keeping up
with the radar data which is on the order of 5 to 6 minutes
is no problem.

The gdradr.html page is running on a 4 cpu SUN E450 which is
handling lots of data relay, data decoding, DODS servers, LAS servers
and other non UNIDATA stuff. I have no problem running the same 
scripts here on out pentium running X86.

The plotting with gdplot2 is a little slow, so I've added a
fill option here with just filling in the grid boxes (which are small),
rather than using the filled contours. But, primarily, it
just takes a while to run through 360,000 grid points.

Steve Chiswell
Unidata User Support


On Wed, 2 May 2001, Gregory Grosshans wrote:

> Steve,
> 
> Scott Jacobs indicated you provided the GDRADR program to CDB.  I also have 
> looked at
> the various web pages you create containing the mosaic data.  I'm curious as 
> to how
> long it takes to process the .9km mosaic over a portion of the country?   Did 
> you ever
> time it for the whole CONUS?  What type of machine are you running this on?
> 
> Thanks,
> Gregg
> 
> Steve Chiswell wrote:
> 
> > GEMPAK users,
> >
> > I have made the Unidata distribution of GEMPAK 5.6.C.1 available
> > for download in source and binary formats.
> >
> > New programs included are:
> >    gdradr: creates gridded composites from NEXRAD products.
> >
> >    gptraj: plots trajectories from gridded data sets.
> >
> >    dcsvrl: decodes SLS watch bulletins (see pqact.conf example).
> >
> > New features:
> >    dcuair: decodes dropsonde and ship soundings, stores maxwind
> >            and tropopause groups, stores raw text portions (see pqact.conf 
> > example).
> >
> >    extended zoom: CURSOR GAREAX
> >
> >    latlon: new labeling options
> >
> >    file aliasing extended in additional grid programs
> >
> >    Added ~250 additional stations to sfmetar_sa.tbl
> >
> > -----------------------------------------------------------------------------------
> >
> > For information on New features, see:
> > http://www.unidata.ucar.edu/packages/gempak/GEMPAK5.6/whats_new.html#5.6C
> >
> > Also, the 2001 package training workshop dates have been announced.
> > For more information see the online registration page:
> > http://www.unidata.ucar.edu/workshops/Training2001/enroll_wkshop01.html
> >
> > Steve Chiswell
> > Unidata User Support
> 
>