Plotting contours with station data...

[Daniel Leins]

Thanks for the help, I've gotten somewhere, but not all the way yet.
This is where things stand.

I researched the archives, and found that it was possible to create a
dummy ctl file so as to define the grid needed by oacres.  The dummy
file, foo.ctl, I created is as follows...

dset foo.dat
options template
undef -9.99e33
title dummy control file
xdef 360 linear 0 1
ydef 181 linear -90 1
zdef 1 linear 1 1
tdef 1 linear jan0000 1yr
vars 1
dummy 0 99 dummy variable
endvars

In grads, I open foo.ctl, I open my real control file metar.ctl, then d
oacres(dummy,ts.2), and I am returned with a message of:

"Warning from OACRES: Less than two stations, Grid will be all missing
values Cannot contour grid - all undefined values"

I saw this same error message in another posting, but no one was able to
provide any feedback.  Does anyone know what might be causing this
problem?  I've certainly got a lot more than 1 station's worth of
temperature data ready to plot.

Thanks,
Dan Leins


Jennifer Adams wrote:

> Hi, Dan --
> You have to use the GrADS function oacres to interpolate your station
> data values to a grid; then you can draw contours. Also, try the 'set
> gxout stnmark' display option. This will draw colorized dots at your
> station locations that you can control with 'set clevs' and 'set ccols'
> and 'set digsiz'.
> Jennifer
>
> On Jan 21, 2005, at 3:15 PM, Daniel Leins wrote:
>
>> List,
>>
>> I would like to plot a map of temperature across a given area, and
>> contour the data instead of displaying it as numbers.  However, when I
>> try and 'set gxout contour', then display the temperature variable, or
>> any other available variable for that matter, it displays the numbers
>> only with no contours.  I've tried 'set cint 1' , and a number of other
>> intervals, however nothing has worked.  Also tried 'set gxout shaded',
>> and couldn't get anywhere with that either.  The data set is in station
>> data format, and while I am able to display the variables in other ways
>> (i.e. station model output), I can't seem to get anything to contour -
>> which is my ultimate goal.
>>
>> Does anyone have any suggestions as to why this might be happening?  I
>> have included the control file below...
>>
>> Thanks,
>> Dan Leins
>>
>> DSET ^metar_out.bin
>> DTYPE station
>> STNMAP ^metar_out.map
>> UNDEF -999.0
>> TITLE Metar Test File
>> TDEF 1 linear 12z14jan2005 1hr
>> VARS 4
>> ts 0 99 Surface Temperature
>> tds 0 99 Surface Dewpoint
>> dirs 0 99 Surface Wind Direction
>> spds 0 99 Surface Wind Speed
>> ENDVARS
>>
>>
> --
> Jennifer Miletta Adams
> IGES/COLA
> 4041 Powder Mill Rd., Suite 302
> Calverton, MD 20705
>