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Werner,
I looked at the gdcross code, and it does not plot the lowest level
if the surface pressure grid is found. That is, if your have a
PRES%none@0 grid, then the algorithm skips the plotting
of the lowest (1000mb in your case) level of vector data.
I suppose this is done to solve overlapping problems between the vectors
and the terrain that is drawn. However, I do see that data below the ground
is masked anyhow, so we can prbably remove this restriction.
In the $GEMPAK/source/programs/gd/gdcross/gdxdvv.f routine,
There are 3 checks that can be commented out:
about line 163 (depending on the version of GEMPAK you are running)
IF ( havsfc ) i = 2
and approximately line 185:
IF ( havsfc .and. istrt .lt. 2 ) istrt = 2
IF ( lavflg .and. havsfc .and. istrt .lt. 3 ) istrt = 3
Just add a "C" to the beginning of the line.
Then rebuild your gdcross program with:
cd $GEMPAK/source/programs/gd/gdcross
make clean
make all
make install
make clean
To answer your second question, no there is no way to change the
tick mark locations in the X. They are being drawn at the location
of the interpolated points that comprises the plot space.
Steve Chiswell
Unidata User Support
>From: Werner Wintels <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200201090237.g092b5N23379
>
>1. I have the following settings for the gempak gdcross function:
>
> CXSTNS = 80;180>-60;180
> GDATTIM = 890301/0000
> GVCORD = PRES
> GFUNC = omega
> GVECT = vecn(mul(-1,vchi),mul(-10,omega))
> GDFILE = xsec.normalized.gem
> WIND = am1/1/1//.3
> REFVEC =
> PTYPE = lin
> YAXIS = 1013/10/man/1;0;1
> CINT = r
> SCALE = 0
> LINE = 5
> BORDER = 1
> TITLE =
> CLEAR = y
> DEVICE = xw
> TEXT = 1.0
> PANEL = 0
> CLRBAR =
> CONTUR = 0
> CTYPE = c
>
>Everything works fine, but the vector data at 1000 mb is not plotted.
>Is there way of fixing this?
>
>
>2. Is there any way of controlling the tick marks on the x-axis in gdcross?
>
>
>********************************
>Werner Wintels
>Atmospheric and Oceanic Sciences
>McGill University
>Montreal, Canada
>********************************
>