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[IDV #EHW-921191]: IDV problem with smoothing grids

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  • Subject: [IDV #EHW-921191]: IDV problem with smoothing grids
  • Date: Mon, 10 Jan 2011 13:07:01 -0700
> Hi Yuan...
> 
> Using the "Principle of Least Surprise", I would say remove the option
> when you have something over topography, and let people use a formula
> to smooth just the grid they want.
> 
> However, even that might be too much of a "surprise", so I would say
> do what you proposed -- solve problem #1 which would smooth the
> topography, but make sure the user is aware of this (document) and
> give them the formula-based work-around if smoothing the topography is
> not desired.
> 
> Thanks for asking!  See you in a couple of weeks!
> 
> tom

Tom,
    Actually, I am more towards to Don's approach that can be less buggy in the 
future. My feeling is that you
can take either one. I will check in Don's change and hope not making any big 
surprise.:)


Yuan
> 
> On Mon, Jan 10, 2011 at 10:28 AM, Unidata IDV Support
> <address@hidden> wrote:
> >> Hi....
> >>
> >> A user had put a contour-over-topography (model data, 1000hPa
> >> temperatures draped over the 1000hPa height field) and when he the
> >> smoothed the contours using the Control option, the contour display
> >> ended up being re-drawn down at z=0 instead of being 'draped'....
> >>
> >> I talked with Don who said the issue is that "the ScalarMap of height
> >> to Z now points to the wrong parameter, so it does indeed plot at z =
> >> 0"
> >>
> >> I have given the user a work-around for now -- to use the gwfs()
> >> function in the Jython library to create a smoothed grid initially and
> >> drape that over the topography...but perhaps the other should be
> >> fixed...
> >>
> >> tom
> >
> > Hi Tom,
> >      We figured out the problem in the source code, and I checked with Don 
> > about
> > the possible solution. Here is two different approaches, and I would like 
> > to get
> > your opinion.
> >      There are two problems in this ticket, one is the topography field 
> > gets smoothed when
> > user applies any smoothing request, and the second is the topography filed 
> > is no longer valid
> > after the smoothed.
> >      So the first approach is to solve the second problem and ignore the 
> > first one, assuming the
> > user does't care that much. If the user does care, then your suggestion 
> > about the formula is the
> > answer. The second apporach is to remove the smoothing option when you have 
> > something over the
> > topography.
> >      What do you think?
> >
> >
> > Yuan
> >>
> >> --
> >> Tom Whittaker
> >> University of Wisconsin-Madison
> >> Space Science & Engineering Center (SSEC)
> >> Cooperative Institute for Meteorological Satellite Studies (CIMSS)
> >> 1225 W. Dayton Street
> >> Madison, WI  53706  USA
> >> ph: +1 608 262 2759
> >>
> >>
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: EHW-921191
> > Department: Support IDV
> > Priority: Emergency
> > Status: Open
> >
> >
> 
> 
> 
> --
> Tom Whittaker
> University of Wisconsin-Madison
> Space Science & Engineering Center (SSEC)
> Cooperative Institute for Meteorological Satellite Studies (CIMSS)
> 1225 W. Dayton Street
> Madison, WI  53706  USA
> ph: +1 608 262 2759
> 
> 


Ticket Details
===================
Ticket ID: EHW-921191
Department: Support IDV
Priority: Emergency
Status: Open