[IDV #COT-972342]: Loading 3D Fields in IDV

Hi Josh-

> I am experiencing a couple problems when using the IDV.  The dataset in Vis5D
> works perfectly, but in the IDV I have a few issues.  The reason I prefer the
> IDV over Vis5D is that the IDV will automatically create a topography based on
> the WRF Terrain Height field.  Too bad this can't be exported as a Vis5D TOPO
> file.

You'll have to talk to the ARWpost people about that. ;-)  I sent them
a question about getting units into Vis5D files.  But I downloaded the
ARWpost code and it doesn't look like a simple fix (e.g. editing a text
file).
 
> The issues are:
> 
> 1.) I am attempting to plot W (vertical velocities) from the dataset.  After
> 02:12 on the dataset (http://www.meteo.psu.edu/~jmg498/wrfdata2.v5d), the data
> disappears (this occurs with all isosurface values).  But in Vis5D the
> isosurfaces still exist throughout the entire cycle, so I know it's not due to
> missing data.  Any ideas on what may be causing this?

Here are some guesses since I was able to display all timesteps:

Has the "Please wait" message gone away?  It is still rendering while
that is present.

Is your memory maxing out when you create the  isosurfaces?  Do you get
an error in the window you started the IDV in?
 
Do you have Fast Rendering enabled?  That will  speed up the rendering if 
you are in the native projection.

Are you plotting the data in the native projection or over some other  
projection?

> 2.) When plotting 3D flow vectors, even when I reduce the vector size to 1 in
> IDV, the tails of the vectors are still very long.  Is there any way to 
> shorten
> them?  This is a bit of an issue since we're zooming in on specific regions.
> In the 2D U10/V10 flow vectors, this does not happen.  The vector lengths are
> perfect when set to 1 or 2.

If you are running version 2.4 or higher, you can adjust the Range
of the data by clicking the edit icon after the listing in the control
window.  In combination with the size, it will set the size for a default
vector range.  Make the range symetrical about 0 (e.g. -10 to 10).
 
> The best bet would probably be for me to try to convert the ARW dataset to
> GRIB.  But the wrfpost program I found seems quite complicated compared to
> ARWpost and requires a lot more in terms of configuration.  So at the moment,
> I'm just using ARWpost to conver the NetCDF files to Vis5D format.

Yeah, it does look a bit more complicated than ARWpost.  Another option
is to convert to GEMPAK since the IDV reads in GEMPAK grids.  Someone
might already have that code working at PSU.

> Thank you for any suggestions or guidance!  It's greatly appreciated.

Don Murray


Ticket Details
===================
Ticket ID: COT-972342
Department: Support IDV
Priority: Normal
Status: Open