[IDV #LCA-261543]: GrADS .ctl files

Hi Stefan-

> Been testing everything and all seems well so far. Only issue I am 
> getting is when editing derived quantities using the formula editor. 
> When I try to go plot a skew-t or another derived variable, I get a Java 
> heap space error: java.lang.OutOfMemoryError: Java heap space. I am only 
> trying to plot one time step using this derived quantity with edited 
> formula, so Im sure my machine isn't running out of memory(IDV is 
> allowed to use >1GB). I was able to successfully derived theta-e using 
> the formula editor and plot one time step.

I didn't have that issue on my system.  How much memory are you running the IDV 
with? (e.g. what does it show in the memory legend at the bottom of the 
screen.)  Also, how are you starting the IDV? 

Question: are all the 
> temperatures in the formula editors based off of temperature in Celsius 
> or Kelvin? Thanks!

Theoretically, it shouldn't matter.  The IDV will convert to Kelvin for the 
calculations.  If you find that the answers are not what you expect, let us 
know.

Don

> On Apr 21, 2011, at 2:45 PM, Unidata IDV Support wrote:
> 
> > Hi Stefan-
> >
> > On 4/21/11 11:23 AM, Stefan Cecelski wrote:
> >> I'll respond to both of your emails here.
> >
> > that's fine.  I'm using the official Unidata tracking system to
> > document the solutions.
> >
> >> In response to the two concurrent open files:
> >> The .ctl names are different, and access two totally different .dat
> >> files with different file names. The multi-timestep .dat file is
> >> 14.55GB. I also have other 1.33km horizontal resolution files at 37GB
> >> which I will be testing on. I will test to see if I select single
> >> time
> >> steps if it works. Maybe it has to do with opening too much data?
> >
> > Okay. The problem is that the pointers to the data that were beyong
> > 2GB are larger than an integer can hold so it would end up as a
> > negative number.  I made a change to use longs instead of ints.
> >
> > I updated the ncIdv.jar on RAMADDA, so please try that one.
> >
> >> In response to the derived variables:
> >> Thanks very much, this clears it up. The attractiveness in using
> >> IDV for
> >> visualization is the fact that I don't have to script the code to
> >> calculate such things as IPV, Skew-Ts, ect. In fact, I had to write
> >> to
> >> FORTRAN code to make ARWpost output for Equivalent Potential
> >> Temperature. It is a SERIOUS pain in the butt, and would much rather
> >> just have IDV do it! I presume I can manually create functions that
> >> will
> >> select the right variables for derived quantities correct?
> >
> > Here's something you can do (and I didn't know you could do this
> > until I tried ;-)).  From the IDV main menu, select Edit->Formulas-
> > >Edit Formulas->Derived Quantities and then the formula you want to
> > use (e.g. Sounding Data (%N1% & %N2% only)).  In the Formula Editor
> > dialog, click on the Derived Tab. In the Parameters section, add in
> > the parameters that you want on the line under TEMP, DEWPOINT.  I
> > used tc,td.  Click the Change Formula button.  Then, if you have the
> > data source already loaded, you can right click on it and select
> > Reload Data from the pop-up menu, or you can load in a new data
> > source if you didn't have one.  Now, under derived, you should see
> > the old one and a new one that says Sounding Data (tc,td only) in
> > the list (near the bottom).  If you want it near the top, just
> > switch the order of the Parameter lines in the Formula Editor.
> >
> > You'll notice that the next time you go through the Edit->Formulas
> > menu, the edited formula will be tagged with <local>.  You haven't
> > overwritten the system one, just created a local version.  If you
> > mess up, you can always delete that one (Remove Formula button in
> > the Formula Editor) and start again.
> >
> > Don
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: LCA-261543
> > Department: Support IDV
> > Priority: Normal
> > Status: Open
> >
> 
> 
> 


Ticket Details
===================
Ticket ID: LCA-261543
Department: Support IDV
Priority: Normal
Status: Open