Setting GEMPAK Defaults

Date: Tue, 27 Feb 1996 12:01:15 -0700
From: Peggy Bruehl 
To: SOO_STRC Mailing List 
Subject: 960227:GAREA Defaults
Cc: paulw@STRC.pubnwscr.noaa.gov, peggy@comet.ucar.edu

>From: paulw@STRC.pubnwscr.noaa.gov 
>Subject: garea/area defaults
>To: soo_STRC@comet.ucar.edu
>Date: Tue, 27 Feb 96 11:25:25 MST

Paul,

>Can anyone offer any advice?
>
>In gempak the variables garea and area keep in defaulting to wv (West Virginia).

Yes, because the software was originally written at NASA Goddard...in
Washington DC.

>I would like to change this default to something more appropriate for Pueblo.
>I have looked at the documentation and have not found anything obvious
>suggesting how to solve this problem.

The file which defines the absolute defaults for GEMPAK is 
$GEMPDF/gemglb.pdf (/usr1/nawips/gempak5.2/pdf/gemglb.pdf).  To change these 
defaults, simply change the entry for the variable.  For example, change:

PARM    NAME=$GAREA     TYPE=(STRING,48)  DEFAULT="WV"

to:

PARM    NAME=$GAREA     TYPE=(STRING,48)  DEFAULT="CO" 


Sometimes, however, you may want to define some defaults that are
of a "less global" nature.  In this case, you can rely on GEMPAK's
use of "relative" defaults.  When you run any GEMPAK program, the
GEMPAK software comes up with a set of values for each of the
variables used in the program.  To find these default values, GEMPAK
first checks for the existence of a file called "gemglb.nts" in the 
current directory.  This file contains the relative defaults for all
the GEMPAK variables.  If this file exists, all the variables default 
to the values in this file.  Each time you successfully run GEMPAK,
the local gemglb.nts file is updated.  The absolute defaults are 
only used if there is no file gemglb.nts in the current directory.

So, if you find yourself usually running GEMPAK in the same directory,
then setting GAREA=CO once will be enough to set the "relative"
default to Colorado.  However, if you delete the gemglb.nts file,
or you cd to a different directory, you will go back to the "absolute"
default of WV.

Sometimes relying on gemglb.nts just doesn't work very well.  Maybe
you are always running GEMPAK in different directories, or there
are several users running GEMPAK in their own directories, etc.
In this case, you may want to define your own "default file" for
the GAREA and AREA.  Default files have a very simple syntax (see
gemglb.nts or last.nts for examples).  Here's the "default file"
that I use to specify a nice GAREA & Projection for North America
plots:

  % cat $GEMNTS/defaults/area.na
  PROJ    str/+90;-100;0/0;3;0;2  
  GAREA   10;-125;50;-20  

I also have a simple one for Colorado:

  % cat $GEMNTS/areaco.nts
  GAREA   co
  AREA    co
  PROJ    nps

Now, anytime I want to read in my Colorado default area, I simply
use the "restore" command.  Here's an example with GPMAP, the
map drawing program:

% gpmap
 MAP       Map color/dash/width              1
 GAREA     Graphics area                     WV
 PROJ      Map projection/angles/margins     MER
 SATFIL    Satellite image filename(s)       
 RADFIL    Radar image filename(s)           
 LATLON    Line color/dash/width/label/inc   0
 PANEL     Panel loc/color/dash/width/regn   0
 TITLE     Title color/line/title            1
 TEXT      Text size/font/width/hw flag      1
 CLEAR     Clear screen flag                 YES
 DEVICE    Dev|name|X;Y|colormode|plotmode   XW
 Parameters requested: MAP,GAREA,PROJ,SATFIL,RADFIL,LATLON,PANEL,TITLE,TEXT,
 CLEAR,DEVICE.
 GEMPAK-GPMAP>restore areaco  

That's the command.  Note that because I named the file "areaco.nts", I
don't have to type the ".nts" in the restore command.  If I didn't use
the ".nts" suffix, I'd have to type out the full file name.

ALSO, because I put my default file in the $GEMNTS directory 
(/usr1/nawips/gempak5.2/nts), I don't have to type the full path.  
If the default file were in any other directory, I'd have to type 
in the full path.

Now, let's look at what happened when I restored the areaco.nts file:

 GEMPAK-GPMAP>display
 MAP       Map color/dash/width              1
 GAREA     Graphics area                     co
 PROJ      Map projection/angles/margins     nps
 SATFIL    Satellite image filename(s)       
 RADFIL    Radar image filename(s)           
 LATLON    Line color/dash/width/label/inc   0
 PANEL     Panel loc/color/dash/width/regn   0
 TITLE     Title color/line/title            1
 TEXT      Text size/font/width/hw flag      1
 CLEAR     Clear screen flag                 YES
 DEVICE    Dev|name|X;Y|colormode|plotmode   XW

See how my Colorado defaults have been set in the program.

You can now run the program to see the map:

 GEMPAK-GPMAP>run 
Creating process: xw for queue 122707
 GPMAP PARAMETERS:
 Device:              XW      
 Projection:          nps    
 Graphics area name:  co     
 Map:                 1      
 Title:               1      
 Panel:               0      
 Latlon:              0      
 Clear:               YES
Enter  to accept parameters or type EXIT:
 Parameters requested: MAP,GAREA,PROJ,SATFIL,RADFIL,LATLON,PANEL,TITLE,TEXT,
 CLEAR,DEVICE.
 GEMPAK-GPMAP>exit

Don't forget to run GPEND!

% gpend

There are a full set of sample default files for GEMPAK programs 
already included in your copy of NAWIPS 5.2.1.  Take a look at
the $GEMNTS/defaults/ directory.  If you want to use any of these
default files in your GEMPAK programs, you'll have to specify
the "defaults/" part of the full path.  (Remember, you can only
leave off the "$GEMNTS" part of the full path.)  For example:

GEMPAK-GPMAP>restore defaults/area.na

>When I first ran the ro_rtgrids, I had to add the line "garea=dest" in the 
>subroutine which writes the nagrib commands in read_statfile.f.  I am plotting
>only the "main" metafiles, and the plots are OK.

Yes, in the ro_rtgrids scripts, Ron Miller always deletes the gemglb.nts
files, so all the variables must be set each time you run any program.

>Has anybody else run into this problem and how can I change the default?

Let me kwow if you have any other questions,

Peggy
__________________________________________________________________
Peggy Bruehl                     National STRC Coordinator - NWS
peggy@comet.ucar.edu             COMET/UCAR PO Box 3000
(303) 497-8356                   Boulder, CO 80307-3000
SOO/STRC Home Page: 
http://www.comet.ucar.edu/pub_html/STRC_html/index.html
------------------------------------------------------------------

> 
>Thanks,
>Paul Wolyn
>SOO PUB