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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
