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Mike, You can use gdplot2 to save on running gdcntr multiple times. One solution is to split the color bar into >= 0 and < 0 (eg sinking and rising), then start FLINE at 0 for both instances- multiplying negative values by -1. Here is an example: GEMPAK-GDPLOT2>l GDFILE = eta GDATTIM = f000 GLEVEL = 700 GVCORD = pres PANEL = 0 SCALE = 999 GDPFUN = mul(omeg,-1) ! omeg TYPE = f ! c/f CINT = 4;4 LINE = 31 FINT = 1/1 ! 1/0 FLINE = 24-30;8-23 ! 0;23-8;30-24 CLRBAR = 1/v/ll/.005;.05 ! 1/v/ll/.005;.55/.4;.01 TITLE = 1/-1 ! 0 TEXT = .8/22/2/hw CLEAR = y GAREA = uslcc PROJ = lcc/25;-95;25/10;0;0;0 <etc> You could use gptext to annotate the rising and sinking color bars accoringly. Steve Chiswell Unidata User Support On Wed, 25 Apr 2001, hardimanm wrote: > Hey folks, > > I've been building scripts to automate the development of forecast model > fields for web use at Lyndon State College, and have been attempting to > customize certain things. One example is with the 700mb/UVV fields > (example at http://apollo.lsc.vsc.edu/data/web/models/eta/700/06.gif, > http://apollo.lsc.vsc.edu/data/web/models/eta/700/00.gif ). What I > would like to do is to force the yellow color onto the 4-5 field, and > have the other colors in the list all fall into place around that, > repeating if necessary. Right now, the whole color scheme shifts > depending on what values are present. > > For a current temperature chart, I locked in values using the following > input: > > FINT > = -30;-25;-20;-15;-10;-5;0;5;10;15;20;25;30;35;40;45;50;55;60;65 > FLINE = 0;2-21 > > and ran the gdcntr program twice, to cover a range of temperatures > from -30 to 140. I'd like to avoid this, and I think there must be an > easier way than listing every value in FINT. Currently, I'm using the > following input: > > gdcntr << EOF > > GDFILE= $GDFILE > GDATTIM= f$FORECAST > GLEVEL= 700 > GVCORD= pres > PANEL= 0/0 > SCALE= 999 > GFUNC= mul(OMEG,-1) > CTYPE= c/f > CINT= 1 > LINE= 0 > HILO= > HLSYM= > REFVEC= > TITLE= 1/-2/ETA 700mb Vertical Velocity (-ub/s) and Heights (m) > TEXT= 1/3//HW > CLEAR= NO > GAREA= 17;-116;52;-50 > PROJ= STR/90.0;-95.0;0.0 > MAP= 30 > \$MAPFIL= HIPOWO.CIA > LATLON= 0 > DEVICE= GF|$SAVEDIR/$FORECAST.gif|766;587 > CONTUR= 3/3 > SKIP= 0 > FINT= 1/-20/4;5;1/6/40 > FLINE= 2-7;8;9-26 > CLRBAR= 1/V/LL/.002;.05// > > I attempted to force color 8 onto value 5, (color 8 is forced to yellow > using gpcolor later in the script), but it doesn't work. Is there an > easier way to achieve what I'm trying to do? I'd like to avoid having > to list every value on FINT, since there is a 1 unit increment, and the > list would likely run too long for gempak's input, and I'd end up having > to run gdcntr some 3 or 4 times just to get the UVV plotted. > > Thanks for any help! > > -Mike Hardiman > >