20020402: NMAP2 product generation query

John,

I suspect you don't want to use graph-to grid. A quick explanation of
what that is first:

The Graph to grid option allows you to generate a gridded data field
from a set of contours (possible graphically edited). An example of this is
show in my tutorial:
http://www.unidata.ucar.edu/packages/gempak/tutorial/nmap_pgen_grid.html

Yes, you do have to fill in all the fields that you want. The default
is for the QPF and certain forecast hours that the national centers
have to produce products for.  This option allows tou to create
a GEMPAK grid file from contours and labels you have created either through
the PGEN pallet, or from the VG driver from GDCNTR for example, and graphically
edited in the PGEN pallette.

Now, you said you would like to create an augmented display with
map symbols, annotations etc. You already have the grid from NOGAPS,
so you don't have to create one from your analyzed graphical
contours. So, given that, after pulling up your PGEN pallete, you can select 
various line types, text, symbols ets to use to draw on your screen. This is 
somewhat shown
at:
http://www.unidata.ucar.edu/packages/gempak/tutorial/nmap_pgen.html

Once you have your annotations, you can save these to a VGF file using the
"SAVE" or "SAVE AS" buttons at the top of the PGEN pallete. This will 
save a file, typically the "Local" directory is your current working directory.
The VGF file will have georeferenced symbols (not the gridded data itself,
just the symbols created in the product generator).

Now, you can use the created annotations as a VGF file as a data set in 
NMAP2 by exiting out of the product generation pallette and going to 
the Data selection window and selection "new source" and then the VGF
data type. If you saved your vgf in "Local" then scroll down to local
in the selection window and add this to your displayed product.
You can use this VGF file with any data set, not just the NOGAPS grid 
you had displayed when you created the VGF file.

Otherways of displaying the VGF data are to use GPMAP setting the VGFILE
parameter to your vgf file location to display the symbols/annotations
on any of your data sets, including in scripts. This is useful if
you created a vgf file that might show your IOP region, experiment 
boundaries, or other points of interest and you wanted to annotate
products you were creating from a script.

From a GEMPAK program, like GDCNTR for example, you can use the VG device
driver to output your graphics as a vgf file. You can then open
this in NMAP's PGEN pallete just as you can reopen your file of 
symbols/annotations,
or display it through GPMAP, or as a VGF data set in NMAP.

Hopefully this starts you out with how you might be trying to use the
product generation. Let me know if this satisfies what you are trying to do,
or if I have missed the mark on why you were looking at graph to grid.
Steve Chiswell
Unidata User support



>From: John Merrill <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200204022115.g32LFqa24182

>Dear Steve:
>  I've been fussing with nmap2, and have not been able to save a product
>in any useful way. My intention is to augment a display of gridded data
>(from Nogaps fields, annotated with map symbols, text and other tags).
>I'd like to save these for iterative editing, for display, possible
>animation, etc.
>  Well, it fails with perfect regularity. Here are the steps I've used.
>I defined a custom Map, and tailored the gridded file names and the
>appropriate resource files so that the data "show up" in the menus. (A
>lower priority is to decimate the resource files so that "nothing else"
>shows up.) I can dsiplay a map, using a "standard" Gempak script. I use
>the Prod menu key  and select the Graph to Grid Object. The pop=up menu
>allows me only QPF and _none_ as Product options. Trying QPF leads to a
>segmentation fault and consequent core dump. None gives me a table of
>parameters to fill in under "Advanced." But even there the Cycle and
>Forecast Hour menus are not relevant - they don't include the time on the
>frame which I selected and loaded. All of the parameters in the Advanced
>list are blank. I could fill them in; perhaps I could use gdcontour to
>make a similar map, and paste in the corresponding values. However, this
>would be tedious, and I assume that there is a parameter-control file
>which, once its location is know, becomes the golden fleece.
>
>Is there another way to generate or save the kind of product I am seeking?
>I appreciate any help you can provide.             John
>
>
>John Merrill                                     Telephone:  401-874-6715
>Graduate School of Oceanography, URI             Fax:        401-874-6898
>