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[IDV #PKC-150970]: Question about 0-360 grids versus -180-to-+180 grids

> Well, now we know:
> 
> Creating display: Color-Shaded Plan View
> not a cyclic grid
> not a cyclic grid
> 
> The file is at www.marinedataliteracy.org/examples/rtgssthr_grb_0.083.grib2  
> if you wanna give it a shot.   I could have sworn it was a complete globe.
> 
> But wait.  Is GRB the problem?
> 
Murray,

The dataset is globe but not fit into the standard we use in the IDV. 
Basically, the IDV check the first and last longitude and expecting the first + 
360 to approximate
to the last within the 0.0005 range. Your data is within 0.5 range and can not 
be identified as cyclic grid. I am not sure there is anything we can do.


Yuan
> Murray
> 
> -----Original Message-----
> From: Unidata IDV Support [mailto:address@hidden]
> Sent: Wednesday, September 03, 2014 5:22 PM
> To: address@hidden
> Cc: address@hidden
> Subject: [IDV #PKC-150970]: Question about 0-360 grids versus -180-to-+180 
> grids
> 
> Murray,
> 
> Sorry about that. It is "lonFlip(a)". Note that the formula is camel-cased.
> 
> Best,
> 
> Unidata IDV Support
> 
> > I had already been down that road several times last night.  Here's
> > the inevitable result for lonflip(a)
> >
> > Creating display: Color-Shaded Plan View
> > NameError: name 'lonflip' is not defined org.python.core.PyException
> >
> > Is there something I need to activate prior to this?  Or is lonflip(a) 
> > exactly correct?
> >
> > Murray
> >
> > -----Original Message-----
> > From: Unidata IDV Support [mailto:address@hidden]
> > Sent: Wednesday, September 03, 2014 3:25 PM
> > To: address@hidden
> > Cc: address@hidden
> > Subject: [IDV #PKC-150970]: Question about 0-360 grids versus
> > -180-to-+180 grids
> >
> > Murray,
> >
> > In the field selector, go to "Formulas" Data Sources.
> >
> > Select Grids > "Define a grid diagnostic".
> >
> > Select a Display of Color-Shaded Plan View or the display of your choice.
> >
> > Click Create Display.
> >
> > This action will bring forth an input window.
> >
> > Enter the formula "lonflip(a)"
> >
> > Click OK
> >
> > Now select the relevant field in the pop-up "Field Selector" dialog.
> >
> > Click OK.
> >
> > These actions should result in the desired image.
> >
> > Let us know if you have trouble.
> >
> > Best,
> >
> > Unidata IDV Support
> >
> > > Please put an old man out of his misery, and tell him exactly where are 
> > > the grid diagnostic formulas.  Your tool sounds perfect, but I have no 
> > > idea where to look.
> > >
> > >
> > > -----Original Message-----
> > > From: Unidata IDV Support [mailto:address@hidden]
> > > Sent: Tuesday, September 02, 2014 1:31 PM
> > > To: address@hidden
> > > Cc: address@hidden
> > > Subject: [IDV #PKC-150970]: Question about 0-360 grids versus
> > > -180-to-+180 grids
> > >
> > > Murray,
> > >
> > > Question. What projection are you using for your data? If you are
> > > using a lat/lon projection there may be a workaround. In particular,
> > > there is a grid diagnostic formula called "lonflip" that may offer a
> > > solution. From the
> > > documentation:
> > >
> > > "Flip the longitudes in a grid from -180-180 to 0-360 (or vice-versa). 
> > > Only works for cyclic rectilinear grids."
> > >
> > > Best,
> > >
> > > Unidata IDV Support
> > >
> > > > This is very good news.  There is an equivalent "tool" in Saga GIS that 
> > > > works well, and their code is public domain.  Are you interested?
> > > >
> > > >
> > > > -----Original Message-----
> > > > From: Unidata IDV Support [mailto:address@hidden]
> > > > Sent: Tuesday, September 02, 2014 12:05 PM
> > > > To: address@hidden
> > > > Cc: address@hidden
> > > > Subject: [IDV #PKC-150970]: Question about 0-360 grids versus
> > > > -180-to-+180 grids
> > > >
> > > > Murray,
> > > >
> > > > We are in the planning stages here at Unidata to resolve this issue. 
> > > > Unfortunately, it requires "deep surgery" and will take time to resolve 
> > > > so we do not have an immediate solution for this problem at this time. 
> > > > But it will get fixed eventually.
> > > >
> > > > Best,
> > > >
> > > > Unidata IDV Support
> > > >
> > > > > Folks,
> > > > >
> > > > > I have a grib2 file that runs from 0-360, and it's no problem to
> > > > > display or subset any areas that fit within this frame.  But I'd
> > > > > like to display a grid over all of Africa, and that would cross
> > > > > the 360-degree right side.  Is there a control or function that
> > > > > splits the
> > > > > 0-360 grid and combines the halves into a -180-to-+180 map?  Or any 
> > > > > equivalent trick I don't know about?
> > > > >
> > > > > Murray
> > > >
> > > > Ticket Details
> > > > ===================
> > > > Ticket ID: PKC-150970
> > > > Department: Support IDV
> > > > Priority: Normal
> > > > Status: Open
> > > >
> > > >
> > >
> > >
> > > Ticket Details
> > > ===================
> > > Ticket ID: PKC-150970
> > > Department: Support IDV
> > > Priority: Normal
> > > Status: Closed
> > >
> > >
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: PKC-150970
> > Department: Support IDV
> > Priority: Normal
> > Status: Closed
> >
> >
> 
> 
> Ticket Details
> ===================
> Ticket ID: PKC-150970
> Department: Support IDV
> Priority: Normal
> Status: Closed
> 
> 


Ticket Details
===================
Ticket ID: PKC-150970
Department: Support IDV
Priority: Normal
Status: Open