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[GEMPAK #SXW-372000]: NMAP grphgd something other than QPF

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  • Subject: [GEMPAK #SXW-372000]: NMAP grphgd something other than QPF
  • Date: Mon, 22 Jan 2007 15:41:54 -0700
Jeff,

Yes, you will use DISCRETE and DLINES. For the discrete values of 2 and 4 alone,
you should draw your contours with higher values on the RIGHT. That means, for
close contours, you will enclose higher values anti-cyclonically.

You can see my VGF with 2 contours with labels 2 and 4 respectively, and the 
setup
for the product graph_to_grid here:
http://www.unidata.ucar.edu/software/gempak/examples/grphgrd_discrete/graph_to_grid.gif

I have DISCRETE asigned -3=2;3-=4.
DLINES is yes;no (the typical default for directional lines).

After running "make grid" using the cpyfil #A215 (CONUS 20km grid), I have the 
nmap2
display showing the contours:
http://www.unidata.ucar.edu/software/gempak/examples/grphgrd_discrete/graph_to_grid2.gif

Now looking at the grid point values is gdplot2 using TYPE=p, I show
the grid points (scaled by 10**1 to verify the decimal point):
http://www.unidata.ucar.edu/software/gempak/examples/grphgrd_discrete/grid_points.gif

If you want the area outside the "2" contour to be assigned "0" rather than 
missing, you can use
DLINES yes;yes and DISCRETE -1=0;1-3=2;3-=4

Then you will get the points shown here:
http://www.unidata.ucar.edu/software/gempak/examples/grphgrd_discrete/grid_points1.gif

Steve Chiswell
Unidata User Support





> 
> Hi,
> 
> I am looking for a way to create a gridded product via NMAP similar to QPF
> but I don't want grphgd to do any interpolation between contour values.
> For example, I have two contours.  I have one contour with a value of 2
> and one with a value of 4.  I don't want grphgd to interpolate between the
> two rather just give me a gridded product with just 2s and 4s in it in the
> area where I had respective contours.  Is this doable?  Do I use DISCRETE
> and/or DLINES parms in some manner?  Thanks so much for your help!
> 
> 
> Jeffrey M. Vukovich
> Senior Research Scientist
> Visiting Scholar NCSU
> 920 Main Campus Drive
> Suite 101
> Raleigh, NC 27606
> Phone:  (919) 424-4442
> Mobile: (256) 541-4138
> Fax:    (919) 424-4401
> Email: address@hidden
> 
> 


Ticket Details
===================
Ticket ID: SXW-372000
Department: Support GEMPAK
Priority: Normal
Status: Closed